Damaged iPhone

I purchased an iPhone 6 on contract from Vodacom last year in April. After three months my phone was having a charging problem and when confronted by Vodacom by it, they were going to charge me R5000 just to fix the phone because there was a small dent on the side of my phone. I was not even asking them to fix the physical damage but to simply fix the software problem. Now they took my warranty away as per the physical damage and I have tried AppleBerry and a private person to fix my phone but no such luck. I think it is utter nonsense that Vodacom is charging me so much just to fix this phone and I am still paying R500 a month for a phone that doesn't work