Invoice is a copy of reversed original invoice &1

What causes this issue?

You want to delete an invoice document that was created as a copy of a
reversed original invoice. Depending on the message type defined in
Customizing, this message may appear as a warning message or an error
message. You can only continue deleting the invoice if this message is
not an error message.

System Response

By deleting the invoice, you delete all the data of the document copy,
including the reference to the document number of the copy in the
original document. If the document copy is deleted and no valid copy of
the original invoice remains, you can copy the reversed original invoice
again in order to make changes.

How to fix this error?

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.