diff --git a/app/commands/github/team_member/destroy.rb b/app/commands/github/team_member/destroy.rb
index abc23cea05..dafce8782d 100644
--- a/app/commands/github/team_member/destroy.rb
+++ b/app/commands/github/team_member/destroy.rb
@@ -4,11 +4,16 @@ class Github::TeamMember::Destroy
   initialize_with :user_id, :team_name
 
   def call
-    ::Github::TeamMember.where(user_id:, team_name:).destroy_all.tap do
-      User::UpdateMaintainer.(user) if user
-    end
+    return unless team_member
+
+    team_member.destroy
+    User::UpdateMaintainer.(user) if user
   end
 
+  private
+  memoize
+  def team_member = ::Github::TeamMember.find_by(user_id:, team_name:)
+
   memoize
   def user = User.find_by(uid: user_id)
 end
diff --git a/app/commands/github/team_member/sync_members.rb b/app/commands/github/team_member/sync_members.rb
index 2b51e2a483..d09cc4ffd1 100644
--- a/app/commands/github/team_member/sync_members.rb
+++ b/app/commands/github/team_member/sync_members.rb
@@ -17,7 +17,7 @@ def add_team_members!
 
   def delete_team_members!
     Github::TeamMember.find_each do |team_member|
-      next if org_team_members[team_member.team_name].include?(team_member.user_id)
+      next if org_team_members[team_member.team_name].to_a.include?(team_member.user_id)
 
       Github::TeamMember::Destroy.(team_member.user_id, team_member.team_name)
     end
diff --git a/app/models/github/team_member.rb b/app/models/github/team_member.rb
index 139e11fa67..01d0bc72f2 100644
--- a/app/models/github/team_member.rb
+++ b/app/models/github/team_member.rb
@@ -1,8 +1,5 @@
 class Github::TeamMember < ApplicationRecord
-  has_one :user,
-    foreign_key: :uid,
-    primary_key: :user_id,
-    class_name: "User",
-    inverse_of: :github_team_memberships,
-    dependent: :destroy
+  belongs_to :user,
+    primary_key: :uid,
+    inverse_of: :github_team_memberships
 end
diff --git a/test/commands/github/team_member/create_test.rb b/test/commands/github/team_member/create_test.rb
index 0d768d59aa..097de7a27c 100644
--- a/test/commands/github/team_member/create_test.rb
+++ b/test/commands/github/team_member/create_test.rb
@@ -4,6 +4,7 @@ class Github::TeamMember::CreateTest < ActiveSupport::TestCase
   test "creates team member" do
     user_id = '137131'
     team_name = 'fsharp'
+    create(:user, uid: user_id)
 
     team_name_member = Github::TeamMember::Create.(user_id, team_name)
 
@@ -30,6 +31,8 @@ class Github::TeamMember::CreateTest < ActiveSupport::TestCase
     user_id = '137131'
     team_name = 'fsharp'
 
+    create(:user, uid: user_id)
+
     assert_idempotent_command do
       Github::TeamMember::Create.(user_id, team_name)
     end
diff --git a/test/commands/github/team_member/destroy_test.rb b/test/commands/github/team_member/destroy_test.rb
index 7276fd7424..801eccb638 100644
--- a/test/commands/github/team_member/destroy_test.rb
+++ b/test/commands/github/team_member/destroy_test.rb
@@ -5,6 +5,7 @@ class Github::TeamMember::DestroyTest < ActiveSupport::TestCase
     user_id = '137131'
     team_name = 'fsharp'
 
+    create(:user, uid: user_id)
     create(:github_team_member, team_name:, user_id:)
 
     # Sanity check
@@ -15,13 +16,29 @@ class Github::TeamMember::DestroyTest < ActiveSupport::TestCase
     refute Github::TeamMember.where(user_id:, team_name:).exists?
   end
 
-  test "update maintainer role" do
+  test "does not remove user" do
     user_id = '137131'
     team_name = 'fsharp'
 
+    user = create(:user, uid: user_id)
     create(:github_team_member, team_name:, user_id:)
 
+    # Sanity check
+    assert Github::TeamMember.where(user_id:, team_name:).exists?
+
+    Github::TeamMember::Destroy.(user_id, team_name)
+
+    refute Github::TeamMember.where(user_id:, team_name:).exists?
+    assert User.where(id: user.id).exists?
+  end
+
+  test "update maintainer role" do
+    user_id = '137131'
+    team_name = 'fsharp'
+
     user = create(:user, uid: user_id)
+    create(:github_team_member, team_name:, user_id:)
+
     User::UpdateMaintainer.expects(:call).with(user).once
 
     Github::TeamMember::Destroy.(user_id, team_name)
@@ -30,6 +47,7 @@ class Github::TeamMember::DestroyTest < ActiveSupport::TestCase
   test "idempotent" do
     user_id = '137131'
     team_name = 'fsharp'
+    create(:user, uid: user_id)
 
     assert_idempotent_command do
       Github::TeamMember::Destroy.(user_id, team_name)
diff --git a/test/commands/github/team_member/sync_members_test.rb b/test/commands/github/team_member/sync_members_test.rb
index 56243942a0..f1bf759903 100644
--- a/test/commands/github/team_member/sync_members_test.rb
+++ b/test/commands/github/team_member/sync_members_test.rb
@@ -5,6 +5,11 @@ class Github::TeamMember::SyncMembersTest < ActiveSupport::TestCase
     team_members = { 'ruby' => [12_412, 82_462], 'fsharp' => [12_412, 56_653] }
     Github::Organization.any_instance.stubs(:team_members).returns(team_members)
 
+    create(:user, uid: '12412')
+    create(:user, uid: '82462')
+    create(:user, uid: '56653')
+    Github::TeamMember::Destroy.expects(:call).never
+
     Github::TeamMember::SyncMembers.()
 
     assert ::Github::TeamMember.where(team_name: 'ruby', user_id: '12412').exists?
@@ -17,6 +22,7 @@ class Github::TeamMember::SyncMembersTest < ActiveSupport::TestCase
     team_members = { 'ruby' => [12_412] }
     Github::Organization.any_instance.stubs(:team_members).returns(team_members)
 
+    create(:user, uid: '12412')
     create :github_team_member, team_name: 'ruby', user_id: '12412'
 
     Github::TeamMember::SyncMembers.()
@@ -29,6 +35,9 @@ class Github::TeamMember::SyncMembersTest < ActiveSupport::TestCase
     team_members = { 'ruby' => [82_462], 'fsharp' => [12_412] }
     Github::Organization.any_instance.stubs(:team_members).returns(team_members)
 
+    create(:user, uid: '56653')
+    create(:user, uid: '82462')
+    create(:user, uid: '12412')
     create :github_team_member, team_name: 'ruby', user_id: '56653'
 
     Github::TeamMember::SyncMembers.()
@@ -38,4 +47,21 @@ class Github::TeamMember::SyncMembersTest < ActiveSupport::TestCase
     assert ::Github::TeamMember.where(team_name: 'ruby', user_id: '82462').exists?
     assert ::Github::TeamMember.where(team_name: 'fsharp', user_id: '12412').exists?
   end
+
+  test "delete when group does not exist" do
+    team_members = { 'ruby' => [82_462], 'fsharp' => [12_412] }
+    Github::Organization.any_instance.stubs(:team_members).returns(team_members)
+
+    create(:user, uid: '12412')
+    create(:user, uid: '82462')
+    create(:user, uid: '56653')
+    create :github_team_member, team_name: 'prolog', user_id: '56653'
+
+    Github::TeamMember::SyncMembers.()
+
+    assert_equal 2, ::Github::TeamMember.count
+    refute ::Github::TeamMember.where(team_name: 'prolog', user_id: '56653').exists?
+    assert ::Github::TeamMember.where(team_name: 'ruby', user_id: '82462').exists?
+    assert ::Github::TeamMember.where(team_name: 'fsharp', user_id: '12412').exists?
+  end
 end
diff --git a/test/commands/webhooks/process_membership_update_test.rb b/test/commands/webhooks/process_membership_update_test.rb
index 1e2495d048..ab3b14da37 100644
--- a/test/commands/webhooks/process_membership_update_test.rb
+++ b/test/commands/webhooks/process_membership_update_test.rb
@@ -6,6 +6,8 @@ class Webhooks::ProcessMembershipUpdateTest < ActiveSupport::TestCase
     team_name = 'team11'
     org = 'exercism'
 
+    create(:user, uid: user_id)
+
     Github::Organization.any_instance.stubs(:name).returns(org)
 
     Webhooks::ProcessMembershipUpdate.('added', user_id, team_name, org)
@@ -17,6 +19,7 @@ class Webhooks::ProcessMembershipUpdateTest < ActiveSupport::TestCase
     user_id = 12_348_521
     team_name = 'team11'
     org = 'exercism'
+    create(:user, uid: user_id)
     create(:github_team_member, user_id:, team_name:)
 
     Github::Organization.any_instance.stubs(:name).returns(org)
diff --git a/test/factories/github/team_members.rb b/test/factories/github/team_members.rb
index 92440b60b5..5f24915eb4 100644
--- a/test/factories/github/team_members.rb
+++ b/test/factories/github/team_members.rb
@@ -1,6 +1,6 @@
 FactoryBot.define do
   factory :github_team_member, class: 'Github::TeamMember' do
-    user_id { SecureRandom.hex }
+    user { create(:user, uid: SecureRandom.hex) }
     team_name { SecureRandom.hex }
   end
 end
diff --git a/test/models/github/team_member_test.rb b/test/models/github/team_member_test.rb
index bee28d2ff8..a8d4949b7e 100644
--- a/test/models/github/team_member_test.rb
+++ b/test/models/github/team_member_test.rb
@@ -2,10 +2,12 @@
 
 class Github::TeamMemberTest < ActiveSupport::TestCase
   test "user" do
-    team_member = create :github_team_member
-    assert_nil team_member.user
+    uid = "123"
+    team_name = "ruby"
+    user = create(:user, uid:)
 
-    user = create :user, uid: team_member.user_id
-    assert_equal user, team_member.reload.user
+    team_member = create(:github_team_member, user_id: uid, team_name:)
+    assert_equal user, team_member.user
+    assert_includes user.github_team_memberships, team_member
   end
 end