Item has been shipped without using the label

Level 1
Hello i sold an item and I was out of country (Canada) , I emailed my friend the label but i dont know how drunk was or maybe he is not familiar with selling online, he just went and copy the address from.the label and put it in a priority mailbox. Now there is no way to mention. that the item has shipped. Plus OfferUp is saying they will refund the buyer in 2 days. Please help !!!!
Happy new year !
Community Helper
I would email customer support at