diff --git a/packages/server/api/src/app/authentication/authentication.service.ts b/packages/server/api/src/app/authentication/authentication.service.ts
index 931f1f5b4d6..cdd8dac7545 100644
--- a/packages/server/api/src/app/authentication/authentication.service.ts
+++ b/packages/server/api/src/app/authentication/authentication.service.ts
@@ -137,6 +137,16 @@ export const authenticationService = (log: FastifyBaseLogger) => ({
                 imageUrl: params.imageUrl,
             })
         }
+        const existingUser = await userService(log).getOneByIdentityAndPlatform({
+            identityId: userIdentity.id,
+            platformId,
+        })
+        if (isNil(existingUser)) {
+            await authenticationUtils(log).assertUserIsInvitedToPlatformOrProject({
+                email: params.email,
+                platformId,
+            })
+        }
         const user = await userService(log).getOrCreateWithProject({
             identity: userIdentity,
             platformId,
diff --git a/packages/server/api/src/app/user-invitations/user-invitation.module.ts b/packages/server/api/src/app/user-invitations/user-invitation.module.ts
index b11034e9750..646fcf340eb 100644
--- a/packages/server/api/src/app/user-invitations/user-invitation.module.ts
+++ b/packages/server/api/src/app/user-invitations/user-invitation.module.ts
@@ -48,9 +48,9 @@ const invitationController: FastifyPluginAsyncZod = async (app) => {
                 await platformMustBeOwnedByCurrentUser.call(app, request, reply)
                 break
         }
-        const status = await shouldAutoAcceptInvitation(request.principal, request.body, request.log) ? InvitationStatus.ACCEPTED : InvitationStatus.PENDING
-        const projectRole = await getProjectRoleAndAssertIfFound(request.principal.platform.id, request.body)
         const platformId = request.principal.platform.id
+        const status = await shouldAutoAcceptInvitation(request.principal, request.body, platformId, request.log) ? InvitationStatus.ACCEPTED : InvitationStatus.PENDING
+        const projectRole = await getProjectRoleAndAssertIfFound(platformId, request.body)
 
         const invitation = await userInvitationsService(request.log).create({
             email,
@@ -144,21 +144,24 @@ async function getProjectIdAndAssertPermission<R extends Principal>(
     return requestQuery.projectId ?? null
 }
 
-async function shouldAutoAcceptInvitation(principal: Principal, request: SendUserInvitationRequest, log: FastifyBaseLogger): Promise<boolean> {
+async function shouldAutoAcceptInvitation(principal: Principal, request: SendUserInvitationRequest, platformId: string, log: FastifyBaseLogger): Promise<boolean> {
     if (principal.type === PrincipalType.SERVICE) {
         return true
     }
-    
+
     if (request.type === InvitationType.PLATFORM) {
         return false
     }
-    
+
     const identity = await userIdentityService(log).getIdentityByEmail(request.email)
     if (isNil(identity)) {
         return false
     }
-    
-    const user = await userService(log).getOneByIdentityIdOnly({ identityId: identity.id })
+
+    const user = await userService(log).getOneByIdentityAndPlatform({
+        identityId: identity.id,
+        platformId,
+    })
     return !isNil(user)
 }
 
diff --git a/packages/server/api/src/app/user/user-service.ts b/packages/server/api/src/app/user/user-service.ts
index b8f3b1f7e5c..96e96ac583c 100644
--- a/packages/server/api/src/app/user/user-service.ts
+++ b/packages/server/api/src/app/user/user-service.ts
@@ -131,9 +131,6 @@ export const userService = (log: FastifyBaseLogger) => ({
         const usersWithMetaInformation = await Promise.all(data.map(this.getMetaInformation))
         return paginationHelper.createPage<UserWithMetaInformation>(usersWithMetaInformation, cursor)
     },
-    async getOneByIdentityIdOnly({ identityId }: GetOneByIdentityIdOnlyParams): Promise<User | null> {
-        return userRepo().findOneBy({ identityId })
-    },
     async getByIdentityId({ identityId }: GetByIdentityId): Promise<UserSchema[]> {
         return userRepo().find({ where: { identityId } })
     },
@@ -309,10 +306,6 @@ type ListParams = {
     limit?: number
 }
 
-type GetOneByIdentityIdOnlyParams = {
-    identityId: string
-}
-
 type GetByIdentityId = {
     identityId: string
 }