Cancellation nightmare with MTN uncapped LTE

I signed up for an uncapped month-to-month LTE contract with MTN after responding to their online ad. The process to have it online was quick and painless. I later decided to cancel the month-to-month contract after we decided to relocate. I sent an email to mtn in March 2024 to give them notice and they quickly responded with an email instruction from MTN's Noloyiso,on the 18th March 2024 for me to return the router to an MTN outlet in order to effect the cancellation. I returned the router on the same month. I realised that I was still being billed for the contract even after returning the router, which I thought could be part of the notice period. The debit orders however continued and I subsequently reversed with my banking app. I sent an email to MTN asking them why they still debiting my account and was asked for an IMRS number, which I had no clue what it was but apparently the store was supposed to give it to me when I returned the modem, none of which was explained to me to be part of the cancellation process. I called MTN call centre several times only to be tossed around between the retentions department and customer services. Every time I talk to an agent from each department, they refer me to the other, until I insisted on a conference call, which sad to say, yielded no fruit. I got hold of this IMRS number from the MTN store which was in another province since my relocation. I emailed the IMRS number and received no response until I emailed the retentions, customercare and complains departments at MTN and was casually told that the matter will be resolved in 21 days. During this period my other MTN lines were suspended included the ones I gave my children to use when they need to. This was done because I refused to continue paying a debit order that I clearly indicated I'm cancelling and returned their modem as per their own instruction 9 months ago. This level of bullying by MTN was incredible. I must indicate that to this day (9 months later), this matter remains pending. My advise is to keep away from MTN. I have been their loyal client for over a decade without issues and with serval lines on my contract. I wish I could cancel all of them but it will be a very costly excercise, so I will wait out the contracts to end. I previously did a cancellation with another service provider and the process was just as seemless as the sales process, so this cant be too complex a task for a telecon provider as big a MTN to accomplish.