I had that problem once. That time i had just removed the english patch, and had my game in Korean because of that, i fixed it by re-installing it again. I guess that creates a mal function of some sort, re-install the game and don't use the english patch anymore, it only creates problems. That should do it.
i Finally Fixed!... what i did was Reapper Said... reinstalling the whole DBO Game, patching again and everything else... and then use the English Patch again, and everything works fine... i can play Wagu Coins again and also i have english patch installed :D