ADSL Line syncing at correct speed

I have upgraded my ADSL line from 4mb to 10mb uncapped almost a year ago but the highest download speed I get is 5mbps as well as very unstable internet and high latencies when playing games on South African Servers. After numerous calls they have still failed to see to the problem. I called Telkom on the 13/04/2016 to reset ports and even after that the problem persisted. The lady said she would log a fault on my behalf and received the reference number : ***. Two days passed with no feedback and when I checked the status of my fault on [URL Removed] it shows that the problem has been resolved but the highest download speed I get is 4,7mbps, which is highly unacceptable as 10mb line speed IS supported in my region and the price I pay for the package is not nearly worth it.