Purchase order approvals for OO Orders

Hi

We have a Third party manufacturing Vendors to which we send the Outside Operations Purchase order(OO). For this we create a work order and then run the customized version of R31410 which will call to create the OO type Purchase orders.

We have set-up the OO type P4310 version to have the approvals enabled based on Branch Plant approval Route code. But the orders that are getting created are not appearing the PO approval(P43081) screen. I have checked the PO is at correct status 230- Awaiting Approval status, P43081 processing options also has the same status.

And the Purchase order itself has the approval route code populated in the Purchase order header(F4301) but yet they are not going to the F4209(P43081). Can you please let me know what could be the reason.