sync speed changing

I have now struggled for months to have my line fixed. I'm paying for a 4mbps line but it's syncing at 2mbps, and the speed seems to be changing every second or third day, there is not one week that goes by where the sync speed differs from the previous. I also have a problem with line line dropping, that was fixed for maybe two weeks and now i'm sitting in the same boat again. I literally had a 4mbps line for maybe 2 weeks out of the months I've been paying for it. I have logged numerous faults, just to get temporary fixes. I am getting horribly frustrated at the fact that not one person in the whole of telkom can seem to resolve my issue, nobody maybe though to themselves that after numerous faults they should maybe look into it properly and not just reset my ports? I am begging you please sort this out! if it does not get resolved i'll take it as far as I need to until someone decides to sort it out properly.