Material & is blocked (Blocking table has not been updated)

What causes this issue?

Material &V1& (Plant &V2&) which you have processed is blocked by User
&V3&. The system has already made several unsuccessful attempts at
blocking your material in order to correct the lock entries for the
items which you have deleted or changed.

System Response

So as not to delay your work any longer, the system discontinues its
attempts at blocking and does not carry out any correction in the lock
table for Material &V1& in Plant &V2&.

How to fix this error?

Please keep in mind that this lock entry is still active and reserves
quantities for your transaction. Other users will not be able to use
them. You can remove the lock entry rectroactively by saving your
transaction as is, then recontinuing processing.

Error message extract from SAP system. Copyright SAP SE.