Poor Cell C Customer service

I have been a Cell C customer for 20 years. I put myself into debt review three years ago and I am successfully managing all my accounts now and things are getting better. I received my upgrade two years ago while being on debt review, but this time around, after the instrument I received from them died, they have decided that I will not be eligible for an upgrade. My accounts are up to date and have been for 20 years. The worst customer service I have ever experienced.