Furious!!! Feeling ******!

I took out a contract in Dec 2016 the benefit I received monthly was R150 airtime , my contract payment was R500-R530 pp

Dec 2018 my contract ended.I wasn’t in a hurry to cancel it bcoz I would then just pay for the R150 airtime as the device has been paid for,I however went in on 12 Jan to cancel it and they said it will be prepaid on 12feb.End of Jan I was billed R529 and couldn’t understand why because according to my knowledge I should have only been paying for the benefits which was R150, I then went through my statements and tax info and noticed something strange, since I opened the contract, I paid R10 for something called “smart data internet” , however in dec it went to R220 and Jan R307. I immediately called in and spoke to consultant who then forwarded it, the next day another Consultant called and I explained, she then explained that my limit was set for R529, so when my handset was done and paid for , they let me use data initial it reaches R529, I then said to her that that’s impossible because My limit has always been set to R1 which means when my benefits are exhausted, I cannot exceed R1. What also didn’t make sense for me was the fact that my contract ended end of dec, so how could This limit have been implemented if it’s a thing that only occurred after the contract ends???I got soo furious at this nonsense , I then asked about feb because I saw the statement for feb was the same. She then said I had already used R90 of the airtime so she will set the limit to R90 then I’ll be billed R90 for feb, (I receive airtime the 1st of every month and on this day it was the 6th) Once again I have been billed R528... my case no was ********** 212.

This is nonsense to begin with, how do they change these things . From the beginning my limit was R1, how can they change it to R529. They are still over billing me ! I have contracts with 3 network providers and I have never experienced nonsense like this ! This is nowhere in any subscriber agreement.