MTN SIM not working

I am beyond disappointed with MTN network, the consultants on call are no help at all. I recently did a SIM Swap at Menlyn Mall MTN store and my phone was working fine then I realized today when my mom tried to call, I cannot receive calls and when I try to call, calls do not go through. Then when I dial *136# it says invalid MMI code but the mobile network coverage shows the SIM is connected. I called the 135 number then was told to try 083135 which I did then it was call 083135 which I told her that's what I did then it was call coverage number *** where the consultant basically told me I need to do another SIM Swap, apparently my number was last working on the 12th of Nov. I am shocked as I was approving payments last week. Not sure your consultants want to help us or not. I am honestly mad and considering moving to another network with my number.