This error typically occurs when the manager does not have a system user account with MSS (Manager Self Service) access.
Resolving the Error When Setting Up a New System User
Go to Security.
Select Setup, then choose CoreTime System Users.
In the Username field, search for the manager’s employee number.
If the account is not found, create a System User Account using the employee number as the username.
Set the Access Type to MSS (Manager Self Service).
Navigate to the Access Privileges tab and grant the appropriate permissions.