MTN - ****************!

I had a data contract with MTN which expired on 31 Aug 2021. They very kindly informed me on 01 Sept 2021 that the contract had expired and that I would now be changed over to a month to month contract and that the cost would change from R329 to R1642 per month. No warning, it just changed. Busy phoning to cancel the contract and I've been on hold for 47 minutes already trying to get through to retentions. How do they justify going from a reasonable amount per month to subsequently changing it to what amounts to roughly 5 month's rental per month? This is ****************! I have tried to cancel it online but don't know how successful this has been. The online chat is ho help either as all the agents are in Nigeria. I will cancel the contract no matter how long it takes. I had a bad experience with my last cell phone upgrade and will definitely be changing service providers as soon as that contract expires.