ATVDiscounter.com Company sent me a junk moped and won't sell me a new part! Fort Worth Texas

I ordered a moped on EBay from ATVDiscounter, the SC-01 Scooter 2007 150cc Moped Free Shipping $ 898. I received it in fairly good time and everything went well. Less than two months after I start driving it, the rear break assembly pops off while I'm driving it, and get lodged in the rear tire and I almost go @$$ over handlebars. VERY SCARY! I realize I will probably not get a free part or anything and I'm okay with that but I would at least like to buy a new part. I get a few responses from Rob Groves and than all of a sudden NOTHING. I can't get ahold of him at all. I left a voicemail and got no response. I e-mailed SunL, the maker, and they tell me to contact Rob. I can't get a part for this moped so there is no way I can ride it. I'm going to to talk to my Credit Card company because now I have wasted $900 on a moped that I can't even drive!

Shaun
Buxton, Maine
U.S.A.