Is it possible to assign a document sequence number on Purchase Orders

We recently created a Blanket Purchase Agreement (BPA) in Oracle Purchasing module. Each time we create a PO from the BPA, it create a release of a BPA using same PO number as BPA number.

Our business team is requesting a new PO number to be created instead of PO release so are exploring options and one option to enable document sequence numbering on Purchase Order but cannot find that as option and wanted to know if someone has done it or have any suggestions to meet this requirement. So essentially we are looking for another unique number in addition to PO number for every PO.