Order Numbers and Receipt Numbers are all the SAME??

I am pulling receipts for an IRS Audit and I just noticed all of my receipts list the same order numbers. There's a receipt number and an order number, both the same on all of my invoices. I know this won't work with the IRS. I have about 40 receipts across several different suppliers and on the receipts the order number and the receipt are all the same. The order numbers on the actual order review page are all unique but not on the receipts.

Has anyone else noticed this? Any advice on who to contact?