Why is my ping suddenly so high on online games?

There's a bit of a backstory to this one. A couple weeks ago, my family started noticing internet problems. When we would click on a webpage, some times the pictures wouldn't load, or even the whole webpage would fail. But if we just reloaded it, it would be fine. We contacted our internet service provider, and they said we have a "hard wire" or something like that. Apparently there was something on the internet cord that caused it to be interrupted occasionally. So they came, and fixed that a couple days ago. Since then, I've noticed incredibly high ping while playing online games on my PC. When I go to Speedtest.net, it still says i have 60 ping, and my regular download speed. When I download something, It's normal speed. But when I play games, i have 200+ ping, sometimes even reaching 1000. How do I fix this? Do I need to call my ISP back again? Thanks