If you have already logged in but see the LOGIN REQUIRED ACB_ERROR_CODE.10 when calling another API function you may not be managing the sessions properly.
All API calling users have to create a routine for session invalidation.
Below are cases where sessions are invalid:
1. A new login is made every time because the API is misused.
2. The server is restarted often.
3. Cookie value is not refreshed or not updated.
4. A session timeout happens.