Bell review: internet service

My complaint is about Bell mobility who have been charging excessively for a mobile internet service. The monthly prepaid limit was up to $80 per month but after a few months the bills which were paid for by credit card were starting to become much more expensive. One Bill was for $490 and the following month it was double that. Nearly $900. I contacted Bell to ask why they were charging me so much for a service I have hardly ever used. They said my data was exceeding the limit and so I was being charged for overusing it. I then decided to cancel the service but after speaking to various customer service personnel, they cut me off and I had to phone back three times.
I wasn't able to cancel the service as they wouldn't let me so I asked to suspend the account. They are still sending bills every month even though I don't want the service.