Failure to cancel router contract after MTN/Mondo consultant misrepresenting facts

I was contacted by an MTN Mondo consultant, trying to sell an MTN router to me, misrepresenting them by telling me my contract has expired and this contract will replace my current one. On 16 Feb I received my router, just to realize it is a second contract which i didn't want. I returned the router to MTN on 24 February and were finally able to get through to the right people to cancel the contract via the call center on 3 March 2023. Needles to say, they did not cancel the contract and charged me the subscription fee, although I never used it and returned it within 7 days of receiving it. I did not pay the router, only my phone contract, but between MTN and Mondo they combined the 2 contracts on one account, thus they suspended my phone. I had to borrow my husband's phone in order to do my work. I followed up with MTN/Mondo call centers and via emails and phone calls to cancel the router contract. Up to this date 115 days later, more than 5 hours talk time, 20 consultants later and the contract is still not canceled. Somehow, everytime i phone they start the process from scratch and tell me 7-14 working days.