Formal error: Collective bills with more than one item / repetitions

What causes this issue?

You want to post a collective bill, and this bill contains either more
than one line item or a repetition item. This is not permitted: A
collective bill can contain no more than one item and no repetition
items.

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?

INCLUDE NA_SYSADMIN1 OBJECT DOKU ID TX

Procedure for System Administrators

INCLUDE FICA_NA_OSS OBJECT DOKU ID TX

Error message extract from SAP system. Copyright SAP SE.