A&A is at fault for selling a product different than what was sold. If the problem was brought up within roughly a month for example. I think its up to A&A to take responsibility 100%
However waiting 3 months and expecting A&A to agree to a return is insane. Thats far too late to expect a return.
There are lessons and examples to be made from this encounter.
Sell what you have, not what you dont.
Check First thing that its what you wanted. I check all my products the minute i get them.
Its unfair to expect a retailer to accept a return 3 months after purchase without a contract or warranty.