VUMATEL FIBER - SLOW SPEEDS

So I ordered a 20/2 mbps FIBER package with Telkom a few weeks ago. After some hassles, we finally got the fiber up and running. Shortly after that, we noticed that multiple speedtests were showing results of 2-4mbps. So we got on the line with Telkom call centre agents only to be told that the problem lies with Vumatel. Vumatel agents then blamed the ISP.

Long story short, we got a Telkom technician to come out and test the line. He logged into the router and used a "Test account" and speedtests showed the same (slow) results. He concluded that it HAS to be Vumatels fault and that they should come out and test the connection using their equipment. Called Vuma that very day and guess what.... they said it is an ISP error.

I even connected my pc directly to the CPE and speedtests showed slow speeds (youtube and netflix buffers as well). However, on the vumatel speedtest, the speeds are PERFECT? No one seems to know what the problem is? Vumatel REFUSES to send out a technician due to the fact that THEIR speedtest is working perfectly, even though EVERY other speedtest gives different results (while being plugged DIRECTLY into the CPE)

What next?