The Direct Commerce Academy deducted money from my bank account without my authorization or knowledge Internet, Internet

After noticing a suspicious charge on my bank statement I called the number of the company listed on my statement (866) 941-3765.
After telling Melissa my concerns, she immediately told me that I had signed up for this program on the internet. She explained that after the 30 day trial that ended 9/27/10 they started to debit my bank account in the amount of $39.98. I informed her that I'd never heard of her company before and demanded my money back.
After telling me to calm down and call her back when I was calm, she hung up on me.
Question: if I supposedly signed up over 12 months ago, why did they wait until 8/11 to start stealing my money?