FM or BAPI to delete suncontracting planned order

Hi Experts!

We are using BAPI_POSRVAPS_DELMULTI to delete the orders created for 11/30 through /SAPAPO/PPT1:

But, only PReqRel order is being deleted, but not PlOrd.(F). When tried through BAPI_MOSRVAPS_DELEMULTI, we got the below error:

TYPE=031: In-house Production Order

STATUS=3: Sub-contracting

Can someone please help me in deleting both the orders that got created? Your help is highly appreciated.