123helpme.com — unauthorized charge

I used the 2 dollar trial for a homework assignment and canceled immediatley afterwards. My card was then charged the full membership price of 29.95. I did not authorize this and my card was charged regardless of my membership canceling. I did not want the membership, nor did I tell the site that it was ok to charge my account for said membership. I have canceled my unwanted membership as of now. Please refund the charge asap.