Postal code &1 in country &2 is not permitted for delivery

What causes this issue?

The postal code is only permitted for P.O. boxes or major customers.
This check will only run when the flag 'XREGS' (address check with city
file) is marked in the table T005 (country table).

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.