Event allowed in current shift only (There is no active shift)

What causes this issue?

There is no active shift because the system was not able to determine a
shift for the event.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Check whether you have <DS><DS:SIMG.COCF_SN_OP4A>defined shifts</></>.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.