When am doing the planned standard cost roll up getting the item inactive for all the item. Any suggestion or solution to this?

You may have an inactive item in your BOMs

Are you using Advanced BOMs or the old Deprecated BOMs?

@Rich Keller If I delete or reactivate the items? would it cause any error

Technically they could be used on transactions while active. If you don't remove them from the BOM then the costing will also be off.