What is the meaning of Source requisitions from purchase documents flag at Complete Award?

Summary:

What is the expected behavior when "Source requisitions from purchase documens" is checked at Complete Award?

Content (required):

We created a purchase requisition from a smart form that had negotiation required flag checked. After an approval of the requisition, we added it to document builder at Process Requisitions with type as New Negotiation and outcome as Blanket Purchase Agreement. At Complete Award, we selected to create purchase document now and checked on "Source requisitions from purchase documents." After BPA was created and approved, no purchase order was created but instead the requisition was not longer referred to the BPA and pooled back to Process Requisitions with the warning "The requisition wasn't processed into a purchase order because it