No service on phone after upgrade

I am a current client with MTN and have been so for 14 years. Aside from my attempt recently and the previous one, upgrades have been simple, quick and painless.<br> <br> This time however, I have upgraded, but the old SIM remains active and the new SIM remains inactive, despite the numerous attempts at trying to activate it (which, according to the voice prompts, says was completed successfully). I have managed to get hold of the call center agents on the 808 number, to no avail. I am sent around in circles without getting the problem resolved. 808 call center agent says it is a technical problem. I am then directed to the technical support. They see that it is a SIM swap issue. I am directed to the SIM swap department. They say it is an activation problem. I am directed to activate again using the *** number. I \activate"again and turn the phone off again for a further 24 hours to allow for the activation to occur. I still sit with the same problem. I have only successfully wasted my time so far.<br> <br> Is there no way to fix this problem?"""