Telkom not sorting out my problem

I have or am supposed to have a 4mbps line, in December 2015 the line slowed down to 3mbps. I logged a fault and someone came out to me and told me that I am far from the exchange..., I have had this line for years without any problem. The fault was closed without consulting me. Now I am connecting at 2mbps and any page I try and open takes over a minute to open, I called again and logged a fault, 967CRK200116 ..... I cant carry on like this and I am paying for a 4mbps line!!!!