Period-end billing order is missing

What causes this issue?

You wish to bill the contract starting from &v1&. Analysis of the
pre-documents indicates that a period-end billing is required for the
period &v2& -- &v3&. All corresponding period billings have already
been executed. However, no period-end billing order exists. This means
there is an inconsistency.

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?

Contact SAP.

Error message extract from SAP system. Copyright SAP SE.