A buyer cancelled an order right after I dropped off the package at the Post Office. I was able to retrieve the package but I can't cancel the label because the status says shipped. If I refund the buyer in full I am out the shipping. How do I fix this?

How to cancel a shipping label after it was shipped but retrieved from USPS | Ask a Mentor

How to cancel a shipping label after it was shipped but retrieved from USPS | Ask a Mentor | eBay Community