MTN service

I upgraded online in October 2019,the courier company delivered my new handset and there was a disrepebcy with my first name on the invoice not matching my first name on my SA ID. The phone was returned to MTN but I have been charged monthly for the handset ever since. Numerous attempts, telephonically, on FB and in person at MTN stores have not helped, none is able or willing to assist to rectify the issue. I have been a MTN customer since 2004 and this level of service by a corporate is disgusting.