An error occurred when unloading the matchcode ID &-&

What causes this issue?

If the matchcode ID has one of the update types A, S or P (physical
implementation of the ID), matchcode records exist on the database. If
the matchcode ID was created with update type I (transparent matchcode
ID), there is a database view.
An error occurred when you deleted the matchcode records or database
view.

System Response

If there are several matchcode IDs to be converted, the system
continues with conversion of the next matchcode ID. If there is only
one ID to be converted, the system terminates the conversion with an
error message.

How to fix this error?

Find out the update type of the matchcode ID whose conversion caused
the error. Use other means to try to delete the matchcode records
(program SAPMACO) or database view (transaction SE11). You can activate
the matchcode ID with transaction SE11 after deletion.

Error message extract from SAP system. Copyright SAP SE.