I'm not getting any support or help with my Wifi issue

I have been an Xfinity loyal customer for the past 5 years and for the most part my experience has been pleasant.  However for the past month my WiFi has been going on and off every 5-10 minutes interrupting my streaming, tv shows/movies, and work and the outages last from a few seconds to several minutes.  I have had 3 technicians at my home in the past few weeks and this issue still persist.  Every time I call customer support they transfer me around run diagnostics and once done the issue arises before they can even get me off the phone.  I was on hold today over 30 minutes waiting to speak to someone in the advanced technical support department only for them to hang up after the long wait.  Can someone please direct me in the right direction because I am at my wits end and will be forced to cancel the service if this can't be resolved.