A while ago I purchased a gamebit to clean some games with. When it arrived, it would not open the games. It was poorly manufactured, and would not grip at all. I emailed the seller, and he said I could ship it back for an exchange. I shipped it back, and he received it and said he would ship me a new one. It never arrived. I emailed him telling him that, and he said "item lost fully refunding" or something along those lines, which leads me to believe he didn't bother mailing it back because it wasn't worth the extra dollar.
So now I've decided that I need a new gamebit, so I tried to buy from him and this is what it says.
Transaction Blocked
# Unfortunately, this seller has decided that you are not permitted to bid on their listings. You may contact the seller via the Ask Seller Questions feature if you want additional details.

So naturally I'm pretty angry.
Is there any way to change my feedback for this guy? Anyone else have any bad experiences with nintendoplayerschoice?