Sold Item returned unclaimed

[kage9]

I sold an item a couple months ago for $40 free shipping. Packaged was returned to me a couple of weeks ago with a sticker stating it was unclaimed and unable to forward. Buyer has not contacted me all this time. I want to repost the item for sale. What is the statute (if any) that the buyer is able to get their money back from me?

[kensgiftshop]

180 days through Pay Pal.

[mspirit57]

Cancel the transaction with problem with buyer’s address. 

This refunds their $ and allows you to relist the item.