PO receipts

Hi everyone,

I’m facing with a problem:

I created two purchase orders of the same vendor and he delivered both at the same time, with the same receipt and in the same pallet. Is there an standard option to register an arrival with the receipt instead of the purchase order ID? I tried to assign the same license plate ID to both PO, but the system doesn’t let me. Anyone knows what I do wrongly?

Thank you!