Amended Contract

I signed up a new contract with Cell C Clearwater on 2013-09-03 with specific features/benefits however I discovered that my contract was amended and I was charged a higher subscription monthly. I visited the Cell C Clearwater outlet on 2015-10-29 and was assisted by Thabo and explained my case and he immediately contacted some department who checked on their system and confirmed that they could not see who or when the amendment to my contract was done. He promised to investigate the incident further and give feedback within 48 hours. I visited the outlet again on 2015-11-03 and was interviewed by Brian and again I explained my story and was told that Thabo no longer works there, nonetheless he called some department again who informed him that I had requested the amendment in July 2014, this totally untrue. I expressed my disbelief and unhappiness to Brian who just didn't seem to care as he was simultaneously dealing with another client next to me at the same time and said there was nothing he could do. I can only advise other potential customers to carefully consider before joining this cellphone company whose network coverage and service are equally bad.