Latency and Speed Problem

I pay R700 a month for a 4 Mbs Line. The last 2 weeks it never runs at that speed about 2 Mbs now the problem has escalated and my line running at ~0.4 Mbs and to Top it all off a latency of anything from 400~500. This makes playing online games and general browsing a nightmare. Logged a call with Telkom but got 0 response. I need this problem fixed because if it persists I WILL NOT PAY my account next month. I have multiple screenshots of [URL Removed] at ALL hours of the day with no change. You must think we are all idiots but I can see and KNOW something is wrong. Changing ISP has not worked either. Come fix this!!