Modem disconnects when I use webex or zoom for work

I've been tracking my internet connectivity for a couple of weeks. Today for example I ran a speedtest after I logged into work and was above 300Mbps down and 11 up. It was steadily in that range for about an hour. I did notice a little packet loss here and there but speed was high. At 10am I logged into a zoom meeting and within 3 minutes my modem was not connected to the internet anymore. I rebooted and a few minutes later I was back up and running, but at 30Mbps down and 11 up. After a few tests the numbers did not improve. This is what I've seen over and over. I did not rejoin the video portion of the meeting and just remained on by phone.

This has repeated more than 10 times in the last couple of weeks. For the rest of the day I expect that I'll have low speeds and that I'll have a very poor video conference experience that often results in the modem requiring a restart. There is a strong correlation to using video conference and being disconnected.

I've checked my modem, and from my understanding the power and SNR are all inside normal range. I have repeated the above scenario on my work computer over VPN and on my personal computer when connected normally. Wired and wireless. 

My question is - what is going on!? I've chatted and called support and my experience is that folks are willing to try to help but they don't know what to do, and sometimes they disconnect me when they remotely reboot my modem and then they do not contact me afterwards so I don't get to really finish with them. Does anyone have any ideas?