Why does the Gateway keep restarting itself?

Lately, my Internet service craps out and the Gateway light goes red. It then resets/restarts itself. Sometimes 6-7 times per day. Newest modem/gateway Comcast offers. I used that worthless chatbot and finally got an agent to chat with me, but they offered nothing (restarting my gateway from the mothership and then telling me everything works). I have a tech coming in a couple of days, but I don't know what they can offer. Is it a problem with the coaxial cable? Is it outside the house? Anyone else experience this problem? Thanks.