Razer Barracuda X Can't register because I don't have the original packaging or the reciept.

I got the Barracuda X as a Christmas gift about 2 years ago, I just had my first problem with it now, and razer support keeps asking me to register the headphones. I can’t because all I have is the headphones themselves, and not the receipt or box. Also, if I were to try and find proof of purchase, I would need to go through all of my grandmothers purchases from 2 years ago, and she doesn’t know what card she used. What should I do?