I have a 2 mb/s line and constantly get around 0.2

I have a 2 mb/s Adsl line with Telkom as ISP for internet. I can never het more than 0.7 mb/s and mostly it's sround 0.26 mb/s which is useless and totally unsccepyable. I am paying for a 2 mb line ang not even getting half. This has been an ongoing problem fot years. Kindly get this sorted out once and for all ot credit my account for service not received. Landline number is ***.