Why does my internet connectivity turn off every 30 minutes or so?

Reviews say Xfiniti has terrible customer service but fast internet. So far, that's true from my experience. I can never reach a representative during working hours. BUT has anyone had a connection that cuts out every 30 minutes? I'll be doing my thing... trying to get a Doctor to do a visit on Teladoc and then -- bam -- connection is lost. Wifi signal is there but no sites load. I have to turn Wifi off and then back on and then wait... 5 minutes later I've lost my place in line on Teladoc. Anyone else had this issue? How do I keep Xfiniti from dropping every 30 minutes or so?