Basic IDoc type & could not be deleted completely

What causes this issue?

The basic type &v1& could not be deleted completely.
Return code: &v2&
Evaluation of the return code:
(1) No entry deleted from table EDIDO.
(2) No entry deleted from table EDIDOT.
(3) No entry deleted from table EDISYN.
(4) No entry deleted from table IDOCSYN.
(5) No entry deleted from table IDOCHIS.
(6) No entry deleted from table IDOCVRS.
(7) No entry deleted from table EDSVRS.

System Response

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

How to fix this error?

Error message extract from SAP system. Copyright SAP SE.