Just know that when you refund, Paypal keeps your fee.
It probably has no address bc the person sent it from the mobile app. That thing is completely useless.
I'd ask the buyer if they used the mobile app, tell them you need them to update their address or you'll have to refund. If you end up having to refund and have them pay again after adding the address, I ask the buyer to add the .30 fee to their sale price bc the lack of address was their fault for using the mobile app (or not having an updated address).