Change Order created from Standard Forms not routing through approval hierarchy

Hello, We are having an issue when a purchase order created from standard Forms flows through approval hierarchy, but the change order on approval gets self approved with out routing again to approval hierarchy after changing promise date, need by date, item qty etc.. The order status changes to requires re-approval and submitting for approval gets directly approved. AME is used for PO approvals.

This happens only when standard forms are used. BWC routes again through proper approval hierarchy for the change order.