Unable to fix 10Mb ADSL line

I have been paying for a 10Mb ADSL line for over 4 years, but never achieve more than 2Mb connection speeds. I log a call on a monthly basis to have this fixed. Each time the call is "resolved", a.k.a closed, without any change to the actual speed. It is insanely frustrating

There are multiple conflicting stories each time - there is a line fault, no their isn't a line fault, we're resetting your port and not much else we can do, you're paying for 10Mb but were never set up as 10Mb, oh yes you are definitely set up as 10Mb etc.

All I want is to run at the speed I am paying for. The alternative is to be downgraded and for Telkom to pay back the price difference between a 10Mb line and a 2Mb line for 4 years of billings