Diagnosis
Either you have not maintained the reel category &V1& in Customizingfor the reel calculation or have not assigned a reel category.

System Response
The reel calculation will not be executed unless you assign a validreel category.

Procedure
Assign a valid reel category, or maintain the reel category &V1& inCustomizing for the reel calculation under Logistics -General -> Reel Calculation -> Set Plant Data(Navigation Reel Categories).