how to define parameter based DFF in selfservice procurement

Hi,

We have a requirement we need to create a DFF at PR header level, the DFF will bring only the department (values) for the respective BU. for example there are 3 different BU each have different departments, only the relevant department values will show for each BU in the DFF.

We already doing this at the purchasing header level DFF but same thing we cannot achieve it in the PR.

because we cannot use the bu_id=:{PARAMETER.RequisitioningBUId} for the PR header DFF as it can only be use for the PR line DFF.

Parameter Syntax
Requisitioning BU ID :{PARAMETER.RequisitioningBUId}