WORST SERVICE PROVIDER EVER !!!!

I am so fed up with MTN its the worst network ever , my account was overdue I made payment on Saturday 11/09/2021 at an MTN store , after making payment my phone hasn't been working I can't receive calls or sms's my network is completely off , I've called numerous times between Saturday, Sunday and Today , everyone gives me different stories telling me I must switch my phone off and back on again but still nothing is happening , no one is willing to get to the bottom of the problem and they constantly tell me is they can see my line is active !! , others are telling me to do a Sim swap like what the hell why should I do a sim swap there is nothing wrong with my simcard and if there is they are responsible for the **** that is happening , I am highly upset as I have been tolerant for far too long now

I need this sorted out TODAY STILL or they need to cancel my service immediately and I will not okay a cent more !!!