Charged R400 at the end of "free trial"

I'm a very unhappy Shaw Academy trial customer after being charges R400 by Shaw Academy today when the telephone consultant had assured me that if I cancelled my subscription exactly today, I wouldn't pay. I cancelled today, and apparently, my subscription cancellation is only effective as of 6 July? I'm very upset about this because they are forcing me to pay for a service I don't even want to use any longer. I honestly feel ****med and this is putting me off ever signing up for anything or recommending Shaw Academy to anyone I know ever again. If someone is going to have to pay at the end of a trial, you have to let them know before they sign up. This is exactly why I was sceptical about signing up for the trial. Even my telephone record would prove this. Yet their consultant convinced me that I wouldn't pay a cent at the end of this four-week trial. If I was meant to cancel before today, this is something he should have told me about.