I really hate this company

I wish this company had not taken over MTN contracts because I've been using MTN for years and have always been happy. I ugrade my contract every 2 years and For the first time I had to do my upgrade with Mondo and not MTN, I wasn't happy about this as I had ******* service from them last year when trying to get a new phone so I had to get a new phone elsewhere in the end. but I wanted to keep my data contract with MTN, they messed up the upgrade, and debited me a pro rata fee which makes no sense on an existing contract. The only positive about this company is a call centre agent named Kyle, I called in furious and he was very helpful and understanding. I would have cancelled there and then if he had not assisted me