ISO code &1 is not clear and unmistakable

What causes this issue?

The ISO code &V1& exists more than once in the country table.

System Response

Warning

How to fix this error?

Check your country settings. You may have to delete multiple
occurrences of the ISO code &V1&.
<DS:TRAN.OY01>Proceed</>

Error message extract from SAP system. Copyright SAP SE.