Repeated internet interruptions

Hi - We had an Xfinity outage in our area about two weeks ago.  I hadn't noticed any problems before that but I got an alert from Xfinity about it.  Service was interrupted for an hour or two before it was restored, no problem.  Ever since then, my internet keeps repeatedly dropping signal for 5-10 seconds every 10-15 minutes.  It's enough of a disruption that if I'm on a Zoom call for work it will freeze then drop the call, any online gaming will drop me from the game, and browsing on websites often will give an error and need to be reloaded.  This is happening across every device in our house.

I have the gig speed internet and modem provided by Xfinity.  I've tried resetting that a couple of times but it has no effect. I've also gone through the online troubleshooting tool but that never seems to recognize any issues.  I'm obviously not an expert but it seems like something may have gotten messed up when they fixed the outage in our area.  Any ideas on what else to try?  Our TV service doesn't seem to be affected by this.