Consolidation unit &1: Two-way elimination without partner unit

What causes this issue?

The current document row in the &V1& consolidation unit for two-sided
elimination (that is, on account assignment level 20 or 22) does not
contain any information about the partner unit .
In postings for two-sided elimination, the partner unit must <ZH>never
</> be initial.

System Response

The system prevents the posting of the inconsistent document and
triggers an error message.

How to fix this error?

If you want to enter the current document as a manual posting or by
means of flexible upload, enter the missing partner information on the
user interface for manual posting or in the upload file.

Procedure for System Administrators

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

Error message extract from SAP system. Copyright SAP SE.