Very Poor Service of ADSL line

So, i have been paying a ISP for a 4mb line for about a year now, with telkom telling me that i can handle up to a 4mb line, Turns out after a year of complaining to telkom that my line in faulty with ping of about 500 +, can in fact only support 2mb and not 4, and I've got the telkom guest account screenshots with speedtests to prove it, so i have been paying for a to high internet package for more than a year and the only thing telkom had to say was that they cant do anything about it?<br> <br> Not only if that is enough, but now i have downgraded to a 2mb line and the problem still persists? with ping still being more than 500 and speeds of about 400kb/s and this on a business line.<br> <br> i think this is very poor service and Telkom should be ashamed of it, making customers pay extra for a whole year then not owning up to their mistakes....