SAP Message W/177 - Price phase &3 for material &1 &2 not deleted; it is already activated

Diagnosis
The price phase with the start date &V3& for material &V1& &V2& cannotbe deleted because it has already been activated.

System Response
The price phase is not deleted.

Procedure
Create a new price phase with the requried start date and price. Thenactivate the new price phase.