DISGUSTING SERVICE FROM MTN

I bought a temporary phone that requires that I update my sim card from the small card to the normal one. I have since bought 5 sim cards and have not been successful since. I have sms'ed and followed the prompts. I have called MTN tirelessly and can never get through to someone - even on their Whatsapp chat line. The service is terrible and surely this self-service has not been thought through if consumers are unable to do something as small as a sim swap.