Table & is blocked by another user

What causes this issue?

The table &V1& requested by you for processing is already being
processed.

System Response

The table is currently blocked for other processes.

How to fix this error?

With transaction SM12, you can display who is currently processing the
table and get in touch with him/her.
Enter 'RSTABLE' in the field 'table name', enter the table name &V1&
followed by '*' in the field 'block argument', and remove the name in
the field 'user name'.

Error message extract from SAP system. Copyright SAP SE.