Not getting help

I had contract with Cell C which ended in Dec 2015. My request was to get a proof of payment that Im not owing or letter stating that its finished. When I called into Cell C I was transferred so many times and still havent been assisted with the matter. One of the agents even dropped the call while transfey me, another department takes over an hour just to answer my call. I am appauled by the lack of service and the time wasting that they did !!!