Bad line speeds

Very bad signal buffering all the time, last week logged a complaint and it seems like the usual response. Will get back to you shortly. Nobody bothered to me yet still waiting. Got 40mb line speed, when checking the line speed, I get about 80Kb. this is when I buffer. So why cant I get what I am paying for. Another issue is my wifi on the device stops working and I have to phone and spend 20mins to get it working again as its blocked. this happens at least twice a month, and you cannot change the wifi device it has to be the supp**** device