Making fields Read only in Change assignment using VBCS

Summary:

Hello Experts,

We are trying to make "Business Unit" and "Position" fields under Change Assignment transaction (When and Why) as "Read only" through VBCS but the fields are still updatable. Also, we made the below fields on Assignment page when we perform Change Assignment transaction as "Read Only" but still they are updatable.

Grade, Grade Ladder, Standard Rate/Step, Working at Home

Thanks,Mamta

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