Withholding tax type &1 does not correspond to a unique tax line

What causes this issue?

If we don't have a unique line in the NF-relevant tax results that
corresponds to the specified WHT type, the collection code and tax rate
cannot be determined uniquely.

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

System Response

The system cannot determine the withholding tax rate and official
collection code for the withholding tax type <(>&<)>V1&.

How to fix this error?

Check Customizing of account keys modifying WHT base amounts.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.