HIgh ping

I have been experiencing high ping lately and I can not figure out why. Over the past month or so my ping has drastically dropped, it was at a high of 40-50, but now it is stuck at anywhere between 80-120 with constant spikes to anywhere between 300=400, and sometimes even reaching into the thousands. This has made it impossible to game and it has made using any other thing on the internet slow. I recently had a technician come to my house to see what the problem is, and he said the issue was just a bad connection. But whenever I use an Ethernet cable and plug my laptop into the modem, I end up with the same issues of around 100 ping with massive spikes. While checking my ping on speedtest.com it says that my ping is fine around 55, but when I go to fast.com my ping is at 110-120. I was wondering if there was anything anyone can do to help out or try and tell me what to do to fix the problem.