SAP Message BRAIN258 - Key figure &1 &2 is not correctly defined.

Diagnosis
In the key figure &V1& &V2&, quantities and amounts are added.

Procedure
Chekc the definition of the calculated key figure.
If this addition is still meaningful and wanted, you can hide thedimensionality of one or both parts of the output with the operator'NODIM'. The system then understands this part of the output as adimensionless number.