Moved to a month to month contract without my permission

I had a data/router contract with Mtn that was supposed to end 31 Nov 2021. Fine. No one contacts me to prior to this to let me know of alternative data contracts etc. Not that I was looking for alternatives. I was happy with the contract ending.

On the 2nd of December I receive an sms claiming that I have been moved to a month to month contract. I did not agree to this and I did not want it. I was not made aware that this happens at the end of contracts.

Now I am stuck with a contract that I did not want. I am not happy with this at all. When I call in to find why this is happening, they say I can cancel. I agree to cancel. I am then told that oh no you were supposed to give us 30 days in advance. You will still get billed for this.

I am like how? I did not agree to this. How am I paying for something I don’t want? Bear in mind I blocked my router a while back as it was ******. I am not using it.

I am not happy with this and I would definitely not be recommending mtn to anyone!