Requisition to PO Automation not working any longer

Summary

Requisition was created and approved, but the PO's are no longer getting generated

Content

When we created the requisitions with the 'Negotiated' box checked, backed by Buyer Assignment Rules for the category, the PO was automatically generated till we had the 19C. We are not able to see this happen automatically since the last day or so.

The requisition is picking up the buyer name correctly, but not progressing to the Purchase Order. Upon navigating to the 'Process Requisitions' task, the Requisition is not available for processing into the PO, nor do we see any incomplete PO's created for the requisition in question.