Buyer asked to upgrade an item from first class to priority after he'd already paid

[blessedmom23greatkids]

An item I just sold was to be shipped first class at the buyer's expense. He paid it and then a few minutes later he sent a message and asked if I'd be willing to change the shipping method to priority mail, at his cost. I said yes as I hadn't printed the label out yet anyway. 

I could not for the life of me figure out how to invoice him for the shipping difference, whether on eBay or PayPal. And on PayPal I could not see the buyer's contact info to invoice him.

I wound up eating the difference since I'm in a rush to get this printed out. However, for my future reference, is there a way to make this work?

Thanks!

[disneyshopper · Accepted solution]

Log into Paypal.  Locate the original payment.  Scroll down to ISSUE A REFUND.  You will then get the buyer's Paypal email address.  Cancel out of the refund.

Now go to REQUEST MONEY and send an invoice for the additional cost to cover Priority shipping.  Do that now.