Bad customer service

I entered into a contract with mtn for data bundles which amounted to R299. Few weeks ago i received an invoice of R1165.00 i immediately called customer service for assistance. I was referred to one person to another without any assistance. I then went to the store for assistance but i was told a query has been made and it will be resolved within 72 hours. When i realised that i did not get any response i called today and i was told that there is nothing they can do to assist me what i have to do is to pay the amount so that i can be able to cancel my contract. And that if i dont pay until the 10th of September 2022 i will be billed the same amount again. I am so confused and suprised as to how did the amount gets to R1165 from R299. I took the contract of R299 because it was within my budget and im asking myself as to how did mtn get to charge me such amount without my knowledge. So in essence they do not care about our financial wellbeing all they want is to make money. I am so frustrated as no one is assisting me in cancelling my contract as i cannot afford such money.

Agree and frustrated customer