Getting a refund on opened software? Not anywhere I've been in the last decade around here.
Go to any store that sells computer software & they invariably include the clause that opened software can only be exchanged for the same title if the purchased copy was physicly damaged when you opened it, otherwise they don't give refunds nor even store credit.
BestBuy, NewEgg, Target, Walmart, etc have all refused to accept opened software since long before I went blind ~6 years ago, and I doubt they've changed their policies since.
They claim it's to protect against folks buying it, taking it home, opening & copying it, then bringing it back as "defective", only to go home & play their "free copy". The companies have a point & it's a massive PITA should you get your supposedly "new & unopened" title home only to find out the hard way that the jerk whom bought it before you has already used the reg code / DLC codes / etc, and the store simply re-shrink-wrapped it without any clue.
So not sure where you live that allows the return & refund on opened software, but that's not been true in America for a very long time.