Wasn't sure of the appropriate place for this buuut...

Ok, so I have an issue with a 2800 Microsoft Points card that I bought. It seems the card was not activated at the register. I took it back to the store, just a local game place, and they refused to do anything for me. They told me to call Microsoft support. I had a long conversation with them and they told me to fax them the receipt and front and back of the card. First off, I don't have a fax machine. Secondly, I realize that I handed the receipt to the guy at the store when I tried to take the card back, and he didn't give it back when I left. I went back to the store again and they no longer had my receipt. So now they won't help me and microsoft won't help me since I can't prove I purchased it. Is there any other way to activate this card so I can use it? Or am I just out 40 bucks now?