SAP Message AJ193 - A rate determination already exists for rate type &1 and rate category &2

Diagnosis
You attempted to define a rate determination for rate type &v1& andrate category &v2&, however, a rate determination already exists forrate type &v1& and rate category &v2&.

System Response
Processing is canceled.

Procedure
Select the Change function for rate type &v1& and rate categoryV2.