Appalling Service from Discovery Insure

After 3 unsuccessful attempts of calling in to Discovery Insure and being assured on each occasion of having my excess premium charge reversed downwards (after I was sent a revised policy doc) I have no choice but to cancel my policy. On the 24th of I spoke to P Magthala, on the 30th of Sept I spoke to S Maduna on the 12th of Oct I spoke to K Maphogo each of whom assured me of a response within 8 to 72 hours. I have reached a point of total frustration with their empty assurances