Debugging mode via status tracking of POS interface

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.

System Response

When you select this option, the relevant status item line is updated in
the POS interface after every IDoc record is updated. This ensures that
should the program abort, the system is able to determine the exact
key entry that was last prepared in the last IDoc to be processed before
the program terminated. Normally the POS status tables are only updated
when an error occurs that has to be logged or when the system finishes
preparing the IDoc.
If the program terminates, you can determine via <DS:TRAN.WPER>
Status analysis of the POS interface</> which IDOC was last prepared for
the store before the program terminated. The data concerned is then
re-transferred by a direct request in error analysis mode and the
point of termination can be determined using the status analysis.

How to fix this error?

Error message extract from SAP system. Copyright SAP SE.