Proportion Change &1: Auto apportionment not possible [&4]

What causes this issue?

You have made a proportion change from &V3& to &V2& for consolidation
unit &V1&.
Because of the posting to the partner unit, the system cannot correct
proportions on the documents posted in prior periods automatically for
entry &V4& in the reclassification method.

System Response

When you reclassify to the partner unit, the link between the
triggering consolidation unit and the target unit is lost and
corrections cannot be made automatically.

How to fix this error?

Check the documents concerned and correct the posting manually if
necessary.

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.