Not possible to (uniquely) determine user group

What causes this issue?

The system could not determine a user group for your user, or your roles
mean that you are assigned to multiple user groups from which no unique
selection is possible.

System Response

It was not possible to execute the appropriate function.

How to fix this error?

Contact the system administrator to ensure that the necessary assignment
is made.

Procedure for System Administrators

The user requires an FS-PM user group that can be set at role level or
at user level. If the user is assigned to multiple roles and if the user
groups are set up with roles, you must ensure that only one user group
appears for each user.

Error message extract from SAP system. Copyright SAP SE.