R800 admin fee to cancel sim only data contract!!

I have a data contract (sim only, no device) with Telkom. For the first 2 years, I had reasonable good coverage. Since I renewed by contract 11 months ago, the coverage has been intermittent and even when I have coverage, the speed is very slow or there is no data throughput at all. I called the call centre mutiple times in Oct - Jan and they could not assist. I have used no data for the 5 months. I have been trying to cancel my contract and was told I need to go to a store. I was interested in an anydata contract but was told they could sell me the contract over the phone but could not cancel my existing contract telephonically! I finally managed to go to a store to cancel. The assistant at the store made no mention of penalty fees. I am now told there is a R800 admin fee - this is not a reasonable amount in terms of the Consumer Protection Act. I have had no data usage for the past 5 months and there is no device involved. This is nothing short of *******. MTN and Cell C only charge for one month and cost of device. Telkom needs to rethink their business strategy - was thinking of installing fibre - no way I will go with Telkom now!