Not possible to set status 'D'

What causes this issue?

A financial document that has already been assigned, has been changed
and is to be set back to active status. This is not possible until you
have actually saved the document.

System Response

The system does not allow you to set status 'D'.

How to fix this error?

Please save the document first, and then set status 'D'.

Error message extract from SAP system. Copyright SAP SE.