Special documents are not reversible

What causes this issue?

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

IF &V1& = 'A'
The document has status 'A' (clearing document).
ELSEIF &V1& = 'B'
The document has status 'B' (reset clearing document).
ENDIF.
Particular documents are indicated by a status. You can see the document
status in the header data of the document in field BKPF-BSTAT.

System Response

The document cannot be reversed.
IF &V1& = 'A'.

How to fix this error?

Reset clearing using transaction <DS:TRAN.FBRA>FBRA</>.
ELSEIF &V1& = 'B'.

How to fix this error?

The document is a clearing document whose clearing has already been
reset. The document does not need to be reversed.
ENDIF.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.