Help !!!!!

So I’m running hardwired Comcast getting 1400 mbps . The problem for about two months is my online play went from 24ms. To now I can’t play a game lower than 36ms and with that it’s unstable. I’ve done tests thru the Comcast app on network it says latency for my network is 15ms. So how do I get my gameplay back down to a playable ping ?