Cell C service is bad and I want my bill adjusted.

I'm having a contract with Cell C, when I got the contract, the plan was supposed to be 20 gigs for R200 including a router only to find out that I'm getting 10 gigs.I only realized 10 months later, i accepted and moved on. On the 28 of February 2025 i called Cell C customer service to find out why is my bill so high. I spoke to an agent that was rude and she spoke over me,her name is Hlengiwe. I asked to speak to a supervisor as the agent was telling me stories about my bill and the discount flactuating, i asked how as I've had the contract with cell c from April 2023 and added a cellphone contract in July 2023, however I've been paying R902. I was advised that there was a price increase which i never got any communication about it no text message or email was sent to me about price change. I insisted and asked to speak to a supervisor she refused up until i told her that i know there's a supervisor on the floor i work for a call center and I'm a supervisor, so i know the trend. I spoke to a supervisor by the name of Lehlohonolo Mdou who said he doesn't know why my bill keep's on fluctuating from R902 to R927 between November and December 2024, from R1002 to R1012 between January and February 2025. I'm not happy with the service, I accepted what I got but now I'm getting billed more and more for what?! I don't. Not satisfied with the service I got from Cell C.