Steps to reproduce:

1. create a new user with role super admin
2. add user to the group no access to frontend
3. try to authenticate with a user and password via api 
   1. this will return user blocked or wrong credentials
4. add user to the group internal
   1. script will work as expected

ZBX-23262

was fixed but seems to be back 

i have solved it with a user role but even here its not possible to remove all access from the uI elements