Internal error: Not all accruals could be distributed

What causes this issue?

The system tries to assign the accruals to the corresponding document
items in the new settlement (taking split criteria into account). If no
business volume lines with the same split criteria as the accruals
exist, a dummy business volume line is created, to which the accruals
are then assigned.
Not all accruals could be distributed. This is usually due to a programm
error, either in the SAP coding or in BAdI-Implementations.

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 for changes to the Business Volume line in BAdI-Implementations
and for SAP Notes.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.