Worst customer service experience ever

Apparently MTN outsources contract upgrades to an *********** business called Summer Mobile. The business is only open during the week and the contact number never gets answered. I was due for an upgrade in August and everything ran smoothly over the phone. Until 3 weeks later when I still had not received my phone. I could not get hold of Summer Mobile. I tried going to an MTN store in Sandton. They couldn’t get hold of Summermobile either. Eventually at the Clearwater store a consultant sent them an email to cancel the upgrade as no phone was ever delivered. They responded to her saying that he would cancel. Fast forward to November - trying to do an upgrade at an I store and it shows on system that I am not eligible for an upgrade. So went to an mtn store to query this. Turns out that my upgrade was never cancelled and that I have been charged for this upgrade since August. Since it’s a weekend not even the MTN consultants can help me. I am hopeful (even though I shouldn’t be) that this will be sorted out next week. Once it’s resolved I wish to cancel my contract with MTN. I no longer want to be affiliated to a company that does not work hard enough to keep customers loyal.