Supply Plan doesn't conisder item relationship (Item substitute)

Hello.

I have a question please.

I am implementing for a distribution company, they are purchasing material in HQ then move them to distribution centers and sell from distribution centers.

I did setup for substitute items, and did what it needs to consider substitution in plan options, but whenever I place the forecast for an item in the DC, the plan doesn't consider the substitute item existence and it requests to purchase original material even though the substitute material exist.

I found that "Item relationship" even not collected in the plan options.

I did the item relationship and make the relationship planned enables, and ran the collection (Complete refresh).