Gateway issues

I've had the modem for almost a month now.  The first couple weeks went by with no issues.  But, since last Thursday, it seems to have issues.

The wi-fi is recognizable and can be saved on devices but it does not connect to the internet anymore.  At times, it will disappear from the wi-fi list completely.

I've had to resort to ethernet and a router.  They work fine but, around every 30 minutes or so, the Gateway modem seems to do a reset of sorts.  Even with the ethernet and router, videos and streams will freeze for about ten seconds and then resume with the gateway reset.

I have done every standard troubleshooting (unplug the modem, app reset, hard modem reset) and the issue persists to this day.