Netgear Nighthawk MR1100-NAS - Random Reboots

Hello, I own a Netgear Nighthawk 4G LTE Mobile Router (MR1100) (MR1100-NAS) (unlocked dual band) that my partner bought me for Christmas a year or so ago.  It has seen some occasional use, but never heavy/ongoing use.  It did not previously have problems.  We're out of town for weeks for a sick family member's medical appointments in a place where the wired internet is 5Mbs/10Mbs on a good day and wireless beats that by miles.  I have to work while we're here

My router:
- randomly reboots, hangs on the loading circle, then reboots again, 3 times total, then turns off
- removing and replacing the battery and plugging it back in restarts the cycle
- occasionally it completes boot and is useable for 20 min.
- I do not notice excess heat and battery seems fine (no swelling and holds a charge, batt. temp is 43C, batt status is "normal")
- I have confirmed in the app that FW is NTG9X50C_12.06.39.00 
- Network is ATT both before and after issues started (router is unlocked global, not ATT variant)
- location is USA

Steps taken:
- reset using pinhole under cover

- unplug/replug
- run with and without battery

- run with cover open/closed to rule out airflow issue

- tried a half dozen chargers with more than enough power delivery (to rule out charger/cable issues)

I'm a bit upset as the M1 was much more expensive than the alternatives and it has not had an excessive amount of usage before problems began.  I'm out in the middle of nowhere and I can't count on this thing to work, despite me having to work.  Definitely sours me on the idea of ever buying a M5 or M6 in the future.

What else can I do to ascertain why the device is not functioning as it should?

- does the router keep logs when it boots/operates?  How can I pull/view these?
- is this FW version known to be buggy?
- Are there any additional troubleshooting steps that I can take?

I very much appreciate anyone who can provide helpful suggestions/assistance as life is quite difficult at the moment and I have apparently placed more trust in this device than I should have.