Hey Pankaj,
Maybe the problem comes from the SC status. The Shopping Cart item gets the technical status 'Follow-on document deleted' (I1115). => the request is open again, the corresponding Shopping Cart item is sent to the Sourcing Cockpit, even if the product category is not sourcing relevant.
Can you please check the OSS Note '1649794 - Status dependent control of Shopping Cart', "deletion" part?
Hope my answer was helpful!
Imre