diff --git a/src/API/TeamController.php b/src/API/TeamController.php
index 1b9bb9e9..ad35fd4c 100644
--- a/src/API/TeamController.php
+++ b/src/API/TeamController.php
@@ -15,7 +15,6 @@ use App\Entity\Activity;
 use App\Entity\Customer;
 use App\Entity\Project;
 use App\Entity\Team;
-use App\Entity\TeamMember;
 use App\Entity\User;
 use App\Form\API\TeamApiEditForm;
 use App\Repository\ActivityRepository;
@@ -201,7 +200,7 @@ final class TeamController extends BaseApiController
      * Update an existing team
      *
      * @SWG\Patch(
-     *      description="Update an existing team, you can pass all or just a subset of all attributes (passing users will replace all existing ones)",
+     *      description="Update an existing team, you can pass all or just a subset of all attributes (passing members will replace all existing ones)",
      *      @SWG\Response(
      *          response=200,
      *          description="Returns the updated team",
@@ -235,11 +234,12 @@ final class TeamController extends BaseApiController
             throw new NotFoundException();
         }
 
-        // cache the current memberlist
-        /** @var TeamMember[] $originalMembers */
-        $originalMembers = [];
-        foreach ($team->getMembers() as $member) {
-            $originalMembers[] = $member;
+        if ($request->request->has('members')) {
+            foreach ($team->getMembers() as $member) {
+                $team->removeMember($member);
+                $this->repository->removeTeamMember($member);
+            }
+            $this->repository->saveTeam($team);
         }
 
         $form = $this->createForm(TeamApiEditForm::class, $team);
@@ -254,14 +254,6 @@ final class TeamController extends BaseApiController
             return $this->viewHandler->handle($view);
         }
 
-        // and now remove the ones, which are not in the list any longer
-        foreach ($originalMembers as $member) {
-            if (!$team->hasMember($member)) {
-                $member->getUser()->removeMembership($member);
-                $this->repository->removeTeamMember($member);
-            }
-        }
-
         $this->repository->saveTeam($team);
 
         $view = new View($team, Response::HTTP_OK);
diff --git a/src/Controller/ProfileController.php b/src/Controller/ProfileController.php
index 8cf17ce5..db6e2d61 100644
--- a/src/Controller/ProfileController.php
+++ b/src/Controller/ProfileController.php
@@ -9,7 +9,6 @@
 
 namespace App\Controller;
 
-use App\Entity\TeamMember;
 use App\Entity\User;
 use App\Entity\UserPreference;
 use App\Event\PrepareUserEvent;
@@ -19,7 +18,9 @@ use App\Form\UserPasswordType;
 use App\Form\UserPreferencesForm;
 use App\Form\UserRolesType;
 use App\Form\UserTeamsType;
+use App\Repository\TeamRepository;
 use App\Repository\TimesheetRepository;
+use App\Repository\UserRepository;
 use App\Timesheet\TimesheetStatisticService;
 use App\User\UserService;
 use Doctrine\Common\Collections\ArrayCollection;
@@ -78,15 +79,13 @@ final class ProfileController extends AbstractController
      * @Route(path="/{username}/edit", name="user_profile_edit", methods={"GET", "POST"})
      * @Security("is_granted('edit', profile)")
      */
-    public function editAction(User $profile, Request $request): Response
+    public function editAction(User $profile, Request $request, UserRepository $userRepository): Response
     {
         $form = $this->createEditForm($profile);
         $form->handleRequest($request);
 
         if ($form->isSubmitted() && $form->isValid()) {
-            $entityManager = $this->getDoctrine()->getManager();
-            $entityManager->persist($profile);
-            $entityManager->flush();
+            $userRepository->saveUser($profile);
 
             $this->flashSuccess('action.update.success');
 
@@ -152,7 +151,7 @@ final class ProfileController extends AbstractController
      * @Route(path="/{username}/roles", name="user_profile_roles", methods={"GET", "POST"})
      * @Security("is_granted('roles', profile)")
      */
-    public function rolesAction(User $profile, Request $request): Response
+    public function rolesAction(User $profile, Request $request, UserRepository $userRepository): Response
     {
         $isSuperAdmin = $profile->isSuperAdmin();
 
@@ -166,9 +165,7 @@ final class ProfileController extends AbstractController
                 $profile->setSuperAdmin(true);
             }
 
-            $entityManager = $this->getDoctrine()->getManager();
-            $entityManager->persist($profile);
-            $entityManager->flush();
+            $userRepository->saveUser($profile);
 
             $this->flashSuccess('action.update.success');
 
@@ -186,7 +183,7 @@ final class ProfileController extends AbstractController
      * @Route(path="/{username}/teams", name="user_profile_teams", methods={"GET", "POST"})
      * @Security("is_granted('teams', profile)")
      */
-    public function teamsAction(User $profile, Request $request, UserService $service): Response
+    public function teamsAction(User $profile, Request $request, UserRepository $userRepository, TeamRepository $teamRepository): Response
     {
         $originalMembers = new ArrayCollection();
         foreach ($profile->getMemberships() as $member) {
@@ -197,18 +194,15 @@ final class ProfileController extends AbstractController
         $form->handleRequest($request);
 
         if ($form->isSubmitted() && $form->isValid()) {
-            $entityManager = $this->getDoctrine()->getManager();
-
-            /** @var TeamMember $member */
             foreach ($originalMembers as $member) {
                 if (!$profile->hasMembership($member)) {
-                    $member->getTeam()->removeMember($member);
-                    $entityManager->remove($profile);
+                    $member->setTeam(null);
+                    $member->setUser(null);
+                    $teamRepository->removeTeamMember($member);
                 }
             }
 
-            $entityManager->persist($profile);
-            $entityManager->flush();
+            $userRepository->saveUser($profile);
 
             $this->flashSuccess('action.update.success');
 
diff --git a/src/Entity/Team.php b/src/Entity/Team.php
index 74d9310b..e88b466c 100644
--- a/src/Entity/Team.php
+++ b/src/Entity/Team.php
@@ -135,22 +135,11 @@ class Team
     }
 
     /**
-     * Indexed by ID to use it within collection type forms.
-     *
-     * @return TeamMember[]
+     * @return Collection<TeamMember>
      */
-    public function getMembers(): iterable
+    public function getMembers(): Collection
     {
-        $all = [];
-        foreach ($this->members as $member) {
-            if ($member->getId() === null) {
-                $all[] = $member;
-            } else {
-                $all[$member->getId()] = $member;
-            }
-        }
-
-        return $all;
+        return $this->members;
     }
 
     public function addMember(TeamMember $member): void
@@ -167,12 +156,12 @@ class Team
             throw new \InvalidArgumentException('Cannot set foreign team membership');
         }
 
-        // when using the API an invalid user id does not trigger the validation first, but after calling this method :-(
+        // when using the API an invalid User ID triggers the validation too late
         if ($member->getUser() === null) {
             return;
         }
 
-        if (null !== ($existing = $this->findMember($member))) {
+        if (null !== $this->findMemberByUser($member->getUser())) {
             return;
         }
 
@@ -185,22 +174,11 @@ class Team
         return $this->members->contains($member);
     }
 
-    private function findMember(TeamMember $member): ?TeamMember
-    {
-        foreach ($this->members as $oldMember) {
-            if ($oldMember->getUser() === $member->getUser() && $oldMember->getTeam() === $member->getTeam()) {
-                return $oldMember;
-            }
-        }
-
-        return null;
-    }
-
     private function findMemberByUser(User $user): ?TeamMember
     {
-        foreach ($this->members as $oldMember) {
-            if ($oldMember->getUser() === $user) {
-                return $oldMember;
+        foreach ($this->members as $member) {
+            if ($member->getUser() === $user) {
+                return $member;
             }
         }
 
@@ -209,12 +187,14 @@ class Team
 
     public function removeMember(TeamMember $member): void
     {
-        if (null === ($existingMember = $this->findMember($member))) {
+        if (!$this->members->contains($member)) {
             return;
         }
 
-        $this->members->removeElement($existingMember);
-        $existingMember->getUser()->removeMembership($existingMember);
+        $this->members->removeElement($member);
+        $member->getUser()->removeMembership($member);
+        $member->setTeam(null);
+        $member->setUser(null);
     }
 
     /**
diff --git a/src/Entity/TeamMember.php b/src/Entity/TeamMember.php
index 67c3d742..4ad4aa04 100644
--- a/src/Entity/TeamMember.php
+++ b/src/Entity/TeamMember.php
@@ -107,7 +107,7 @@ class TeamMember
     public function __clone()
     {
         if ($this->id !== null) {
-            $id = null;
+            $this->id = null;
         }
     }
 }
diff --git a/src/Entity/User.php b/src/Entity/User.php
index a0447b5f..57344bf1 100644
--- a/src/Entity/User.php
+++ b/src/Entity/User.php
@@ -579,12 +579,12 @@ class User implements UserInterface, EquatableInterface, \Serializable
             throw new \InvalidArgumentException('Cannot set foreign user membership');
         }
 
-        // when using the API an invalid user id does not trigger the validation first, but after calling this method :-(
+        // when using the API an invalid Team ID triggers the validation too late
         if ($member->getTeam() === null) {
             return;
         }
 
-        if (null !== ($existing = $this->findMember($member))) {
+        if (null !== $this->findMemberByTeam($member->getTeam())) {
             return;
         }
 
@@ -592,33 +592,35 @@ class User implements UserInterface, EquatableInterface, \Serializable
         $member->getTeam()->addMember($member);
     }
 
+    private function findMemberByTeam(Team $team): ?TeamMember
+    {
+        foreach ($this->memberships as $member) {
+            if ($member->getTeam() === $team) {
+                return $member;
+            }
+        }
+
+        return null;
+    }
+
     public function removeMembership(TeamMember $member): void
     {
-        if (null === ($member = $this->findMember($member))) {
+        if (!$this->memberships->contains($member)) {
             return;
         }
 
         $this->memberships->removeElement($member);
-        $member->getUser()->removeMembership($member);
+        $member->getTeam()->removeMember($member);
+        $member->setUser(null);
+        $member->setTeam(null);
     }
 
     /**
-     * Indexed by ID to use it within collection type forms.
-     *
-     * @return TeamMember[]
+     * @return Collection<TeamMember>
      */
-    public function getMemberships(): iterable
+    public function getMemberships(): Collection
     {
-        $all = [];
-        foreach ($this->memberships as $member) {
-            if ($member->getId() === null) {
-                $all[] = $member;
-            } else {
-                $all[$member->getId()] = $member;
-            }
-        }
-
-        return $all;
+        return $this->memberships;
     }
 
     public function hasMembership(TeamMember $member): bool
@@ -626,17 +628,6 @@ class User implements UserInterface, EquatableInterface, \Serializable
         return $this->memberships->contains($member);
     }
 
-    private function findMember(TeamMember $member): ?TeamMember
-    {
-        foreach ($this->memberships as $oldMember) {
-            if ($oldMember->getUser() === $member->getUser() && $oldMember->getTeam() === $member->getTeam()) {
-                return $oldMember;
-            }
-        }
-
-        return null;
-    }
-
     /**
      * Checks if the user is member of any team.
      *
@@ -750,10 +741,8 @@ class User implements UserInterface, EquatableInterface, \Serializable
 
     public function isTeamleadOf(Team $team): bool
     {
-        foreach ($this->memberships as $membership) {
-            if ($membership->getTeam() === $team) {
-                return $membership->isTeamlead();
-            }
+        if (null !== ($member = $this->findMemberByTeam($team))) {
+            return $member->isTeamlead();
         }
 
         return false;
@@ -830,10 +819,7 @@ class User implements UserInterface, EquatableInterface, \Serializable
         return $this->auth === null || $this->auth === self::AUTH_INTERNAL;
     }
 
-    /**
-     * {@inheritdoc}
-     */
-    public function addRole($role)
+    public function addRole(string $role)
     {
         $role = strtoupper($role);
         if ($role === static::DEFAULT_ROLE) {
diff --git a/tests/API/TeamControllerTest.php b/tests/API/TeamControllerTest.php
index ed6b1a45..4af59300 100644
--- a/tests/API/TeamControllerTest.php
+++ b/tests/API/TeamControllerTest.php
@@ -170,6 +170,13 @@ class TeamControllerTest extends APIControllerBaseTest
         $this->assertNotEmpty($result['id']);
         self::assertCount(3, $result['users']);
 
+        $this->request($client, '/api/teams/' . $updateId);
+        $result = json_decode($client->getResponse()->getContent(), true);
+
+        $this->assertIsArray($result);
+        self::assertApiResponseTypeStructure('TeamEntity', $result);
+        self::assertCount(3, $result['users']);
+
         self::assertFalse($result['members'][1]['teamlead']);
         self::assertEquals(1, $result['members'][1]['user']['id']);
         self::assertEquals('clara_customer', $result['members'][1]['user']['username']);
diff --git a/tests/Entity/TeamTest.php b/tests/Entity/TeamTest.php
index 702a59a7..9f86c94f 100644
--- a/tests/Entity/TeamTest.php
+++ b/tests/Entity/TeamTest.php
@@ -92,6 +92,9 @@ class TeamTest extends TestCase
         self::assertCount(0, $sut->getMembers());
         self::assertFalse($sut->isTeamlead($user));
 
+        $member = new TeamMember();
+        $member->setUser($user);
+
         $sut->addMember($member);
         $member->setTeamlead(true);
         self::assertTrue($sut->isTeamlead($user));
diff --git a/tests/Entity/UserTest.php b/tests/Entity/UserTest.php
index d4bb5c52..dd7fc841 100644
--- a/tests/Entity/UserTest.php
+++ b/tests/Entity/UserTest.php
@@ -449,6 +449,9 @@ class UserTest extends TestCase
 
         self::assertFalse($sut->isTeamleadOf($team));
 
+        $member = new TeamMember();
+        $member->setTeam($team);
+
         $sut->addMembership($member);
         self::assertCount(1, $sut->getMemberships());
         self::assertFalse($sut->isTeamleadOf($team));