my account was charged for nothing

This is a real theft. After signing with Belly Fat Free I was charged what supposed to be a one-time fee, but a couple of weeks later I was charged almost a hundred dollars more by a company named FastTrackToFatLoss. Even though I called them (there was a number left in my bank statement) and left them a message, they still managed to charged me two more times. Moreover, this company never sent me anything. And this makes it a total scam!