CONTRACT NOT CANCELLED

I had two contracts with CELLC which I took out the same time and a month before I cancelled both contracts as per their instructions. It seems only one contract was cancelled and they have been billing me for the past 2 months and when I called in to confirm this I was told that they would have to look at the phone records. I was called again today after I blocked them from deducting from my account and was advised that there was nothing to search for phone records on that cancellation and was put on hold for 16mins as I was transferred to cancellations. I hung up because someone is not doing their job properly and I am being passed from pillar to post.