Here is the answer for
you.https://www.ebay.com/help/policies/payment-policies/offering-buy-sell-outside-ebay-policy?id=4272&st=12&pos=1&query=Offering%20to%20buy%20or%20sell%20outside%20of%20eBay%20policy&intent=buy%20o&docId=HELP1286
Actually you can ask seller to cancel that order for you, but that's not
the thing I would recommend you to do. In this situation, and you also
wanna buy these 2 items, then you just go to checkout and pay. Done!