Unable to make a purchase through PayPal on Apple Pay

I’m trying to make a purchase through PayPal on Apple Payand It won’t let me make the purchase even though I have the funds to do so. my iOS is up to date, I have plenty of storage, and I don’t have an unpaid purchase. It will either say “payment not completed” or “payment failed” Can someone please help I have no clue why this is happening

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