Netgeat AC1600 Router Modem

Netgear AC1600 Modem Router purchased in August 2020.

I am frequently losing internet service. Some days it's up and down and back within 5 minute increments and may do that for an extended period.  Then I'll get a stretch of many hours with no internet issues. 

I've called the internet provider multiple times, and they say the issue is on my end. The router. (Although I note that I have more trouble keeping a connecting during peak usage times. Hmm.)  They say their diagnostics (or whatever) indicate the router is shutting off and restarting repeatedly at times (but if the router is glitching, why wouldn't it glitch constantly?), with some reference to repeated discovery request attempts to get internet IP addresses.

I've doublechecked all power connections for the router -- no issues.  The router/modem is plugged into a surge protector.  I keep thinking it's not the router and probably the internet service (I'm in a small rural mountain community in NM), but has anyone heard of an issue with this model where the router has power glitchesk, which then affects the internet connection?  Is there any way to check for this issue using the Netgear phone app?

On a side note, I have many devices (19) connected to this router. Maybe it's just not powerful enough to handle all my gadgets? If my internet connection is dropping because the router/modem is overloaded, can someone recommend a Netgear produce that would perform better?    

Thanks.