BILLED INCORRECTLY AND MY ROUTER CONTRACT NOT BEING CANCELLED AS REQUESTED

Kindly assist I have a huge challenge with MTN I upgraded my contract with a combo deal of R649 and I was advised that due to new policy I will have to pay R600 for the remaining 3 months to cover the R2100 on my contract before I can start paying for the new one which R649, all of a sudden I have to pay R91128 that was resolved as it was a system error, I ended up getting the combo deal of R648 MONTLY AT MTN Centurion however my problem now is that im being charged for both phones. I also had a contract for R99 for router that ended in September I called mtn on the 12/11/2021 @ 14:44 I spoke to the lady by the surname of Kubheka I requested to cancel my router contract which was already on month to month for my *** number she convinced me that I can opt for R30 upgrade for 2G instead of cancelling I agreed I even mentioned that R30 is not bad it is fine if that is the case. TO MY SURPRISED SHE NEVER DID THAT I called on the 15 November to cancel and requested the number to be placed back on prepaid still that has not been done till today, ANOTHER HEADACHE I RECENTLY GOT FOR THE COMBO DEAL I MEAN HOW? AND WHY IS MTN MESSING UP WITH OUR LIVES? Now MTN is sending from pillar to post to rectify this I was charged for both phones which I was not supposed to be charged for the 083412 as it is a combo deal I was referred to the where I did the upgrade to fix it because the system charged me R458 which I was not supposed to be charged for and send it to her manager to approve it so that they send it to billings to fix that it’s been 3 weeks now since she she saying it’s approved they are waiting for billings to fix my invoice, I’m sitting with two complaints for one company I respectfully request that you look into this matter and resolve it; your response will be greatly appreciated.