Send Instaflex without request

When I checked my VISA account, I found that DDL Instaflex had charged my account with the sum of $74.98 without permission. I immediately phoned their 800 number which I obtained from the internet and, was told by the gentleman (guy) who answered the phone, that it would be automatic once a person had ordered their "free" trial. When I mentioned that I had seen quite number of complaints on the internet, I was told that all those people can't read.
I also mentioned that I had not received any goods for which I was charged, I was told that they wouldn't ship without being paid first.