Acai Berry Detox After order free trail they began to call me repeatedly to "confirm"which I did. But now they are still calling me even when I told them to stop. Now they are charging me for something I never ordered Nationwide

I ordered a free trail of the Acai Berry Detox. I then kept getting phone calls from two different numbers. I usually don't answer numbers I don't know so at first I didn't answer. But they just kept calling over and over so I finally answered. Apparently it was their "order confirmation people". So talk to the guy and "confirmed my order". I told him I didn't want anything else. But then the next day they started calling again and again and again. Kept trying to tell them to quit calling me but they still continued. I even emailed their billing with my information to just cancel everything. I was just tired of all the stupid calls. Then today I get another call from them and then when I checked the credit card I used I found a charge on there for something I didn't order nor wanted. I am just so sick of all this harassment and want them to stop! Please help!