High Latency/Ping issues

So I've been having high ping and latency issues while gaming for 3-4 months now. Even a few weeks before the pandemic it started. For example my ping is fine for about 20 mintues and then just goes up to 100+ms and stays here.When I run ping tests to google for example I have spikes of 100+ inbetween the normal speeds.My upload and down speeds are fine when I run speed tests. I've talked to xfinity twice now. Once on the phone and now with online chat and they just do the usual reseting my modem etc and the person told me that they only send out techs right now for people who don't have a connection. Wondering if I should try changing my modem or maybe a tech here on the forum could have me post my signals to see if theres something not right etc.

Any help would be appreciated.