Cost Scenario - Rollup Costs Error "The items are missing the cost definition."

Summary:

Cost Scenario - Rollup Cost Errors "The items are missing the cost definition."

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As per my customer requirement, the FG is expected to maintain Standard Cost and Components are expected to maintain Perpetual Average cost.

FG Item - Set with Standard Cost profile

Components - Set with Average Cost profile

With above case, when i create a cost scenario for FG item and run Rollup cost, it is erroring :The items are missing the cost definition".

I raised SR for this error and got an update stating i need to still define the standard cost in the cost scenario for the items having average cost already.