SAP Message AH804 - Billing unit of measurement could not be determined

Diagnosis
No billing unit of measurement could be determined from the rateconstellation valid on &v3& for device &v1& register &v2&.
The error occurred in program &v4&.

System Response

Procedure
Check your rate determination (specifically the billing unit ofmeasurement) for the register.
If you are unable to determine any errors, contact SAP.

144644Extrapolation with base period type = 'X'
145309Addit. info on extrapolatn w/ base period cat. ='X'