Check for zero balance cannot be executed

What causes this issue?

After a change, the document can no longer be checked for a zero
balance. There are no tax amounts in the document, since the document
was entered with the options 'Calculate tax automatically' and 'G/L
account amounts are net amounts'. In this case, the document is only
checked for zero balance when it is posted. It is only then that any
rounding differences can be taken into account for the balance check.

System Response

You receive this warning, but the system permits you to change the
document.

How to fix this error?

Check your entries. You can chose 'Cancel' (F12) to return to the
document overview, or 'Enter' to confirm the changes.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.