Help getting started

HI all, I"m sorry I'm asking an noob question. I'm searched the internet for straightforward answers but don't know how to...

I purchased a game on Steam for my son. (Dark Souls remastered). WE can't get a refund because he played it for 3 hours... but it's too much money to throw away. We just want to resell for a portion of the purchase price but not sure the best way...? Help!

 

You could dispute the payment I guess or try to sell it on the sythe market if that works or try to talk to customer service if they can help.