Substitute item usage

 I have a scenario

Finshed good A consists of B & C Parts. For B  there is a substitute of D.

created a Demand for A qty 2. System suggests to peg the 2 of B and 2 of C. I have a one qty of B and one qty of D.

System should use one of B and one of D. Because D is a substitute of B.

setup:

Created Item relationships  ( D is a susbtitute of

Ran the constrained plan with decision rules use substitute items.

I have tried the MSC:  Choice of item for which to create supplies in substitute relationship, Used the three values for the Profile and ran the Plan.