R1100.00 per month for a WiFi package that doesn’t work. Managers / Supervisors refuse to make contact from 31 March

I’ve called in several times for a manager / supervisor to make contact with me. I’ve been told the matter needs to be escalated and I cannot be put through and I’ll receive a call from the relevant person. This is ongoing for 3 consecutive weeks! Paying R1100.00 per month for normal internet (not even fibre) and I don’t have a connection. Router needs to be synchronised while on a call with MTN at least once per day for everything to work. All they say is take out the sim, wipe it off and put it back into the router.