MTN caused a problem with my number that they do not know how to fix

I am unable to receive phone calls from any other netwrk but MTN. I am also unable to receive any sms's or complete any account maintenance on my app. This issue was logged with MTN several times already but it seems they are only interested in making me pay for a contract that I don not have the full benefit of. Completely unacceptable service from MTN. I I had the option, I would give them 0 stars