Disappointed over bad service

I ported from Mtn to Telkom over a year ago and now I regret. Two week ago I had a problem with my internet connection and I had 1G, spoke to more than 5 call centre Agents all giving me different stories and processes to fix it but nothing happened, the last Agent whom I spent about 40 minutes with in a call like other assured me that all will be well but guess what, as soon as the call ended my phone was on "Emergency Calls Only " I am unable to call them from the Sim Card and had to use a different network to call them and again spent another 25 minutes and airtime and the lady just said I need to do a sim swap for what I do not know and I am afraid I might lose the number all together, I have 700mb on that Sim Card of which I cant use and I am willing to port back to Mtn even if I lose that data but again I am unable because the sim card is not working and its my primary number which I have been using over a decade ????This is so frustrating