Performance Transactions in PO_IGT_PERF_DETAIL table have null in PO_DISTRIBUTION_ID column

We are seeing that po_distribution_id column is null in PO_IGT_PERF_DETAIL and not able to link po/invoice distributions to the performance transactions interfaced from G-Invoicing. The table PO_IGT_PERF_TRANS_HISTORY also has po headerid, line id, line location id but no po distribution column. Did anyone have this issue? Is this a data issue or Oracle is not populating po distribution id on performance transactions? For reporting purposes and to derive performance accounting we are looking to derive the po/invoice distribution id. Please let us know if there is a way to derive the distribution.