Very disappointed

I got a letter informing me that my premium was going to change and I asked for a review on the 27th of November. I was assured that my premium would not go up, guess what? I was debited on the 20th using the premium i said i can't afford. From the last year mid year my premium has gone up 3 times.

Please explain why after assuring me my premium wouldn't change to the new one, you still debited me like that.