It looks like you have created a new field in the sales header named "Amount overdue".
This new field gets the Amount overdue from the customer and stamps it on the sales header.
I see a couple of problems with this design:
1. When do you update the field value in the sales header?
If you update on release, your workflow will never start because the value of the field will always be 0 before the release.
2. You can create a sales order when the customer overdue amount is 0 and the approval will not start but, if the amount overdue changes before you ship or invoice the workflow will be pointless because a released order is not subject to approval.
One solution would be to update the new field when you create the sales header. Yet, you will need to find a way to handle changes in the customer balance after the order is approved and released.
Personally, I would use a Power Automate approval workflow and use customer overdue balance as a variable instead of trying to extend a BC workflow.
