Minutes *******

I have been a Loyal Client with Cell C for over 10 years now, I am just very dissapointed and upset, when I did my last contract upgrade, I still have my old phone and simcard, I just updated it to a data package, but all my benefits that i still had just vanished, I had over 5 000 mins left on my previous contract and when the upgrade kicked in all my minutes just disapeared no explantion nothing, I did pay for that minutes its mine and it should remain with me because all the details are still the same the only thing that changes is the contract terms, but what ever is on the contract should remain there I am made as hell, how can they just take 5000 min as if it is nothing this was accummulated over the years for i service I paid for who give anyone the right to just take it away not good business practice