Modem keeps dropping out every 30 minutes. Anyone have any thoughts? I need to be able to work from home, and right now I can't

I just got xfinity internet and every 30 minutes the modem stops transmitting and disconnects. This means I get disconnected from everything and it never reconnects unless I reboot which takes forever.

I have an older home-built almost a year ago that is in the process of being updated but I need the internet to work because I will be working from home a few days a week while I slowly work on the home I inherited.

Does anyone have any ideas, or suggestions? I believe the modem is overheating but I have already found another thread that shows others have had this issue.