Deleting hierarchy w/o deleting transaction data can cause inconsistency.

What causes this issue?

Deleting the investment program hierarchy without deleting the
summarization data that belongs to it can lead to inconsistencies. If
there is still summarization data, it is not possible to run any
reports that use the program hierarchy.

System Response

Processing continues anyway.

How to fix this error?

Delete the program hierarchy only together with the summarization data
or when there is no more summarization data.

Error message extract from SAP system. Copyright SAP SE.