Being Held Hostage with an ISP line

I signed into their website in October to look at Terms and Conditions, next thing I know they've signed me up. I spend two hours on the phone trying to reverse whatever they did, I'm told I there's a 30 day cancellation period even though I didn't sign up or have any fibre with them. Fine I email my cancellation, it's been 4 months, I'm still being held hostage with their ISP so I can't sign up anywhere else. Every month I call and finish my 50 minutes just for nothing to happen. Vumatel also hasn't been very helpful in helping them release my line. Why is it so difficult to get proper service in South Africa, it's like they're doing us a favour!?!!!