Netgear Nighthawk XR500 DHCP error

My Nighthawk is unreliable and its annoyong me.  I am getting random but increasingly frequent network disconnects for DHCP errors (not assinging new or correct IP addresses when leases expire).  My Connections to the router on WIFI or ethernet work but I get a 'No internet' message. WIFI systems all drop at the same time. Wired usually drops later or not at all but is the same. When down, I get a DHCP error from running IPconfig.  Its not the windows WAN / LAN drivers - Apple and Android phones also drop (and obviously they dont use the windows drivers).

So far to resolve this:

Reboot Nighthawk router (sometimes resolves, often doesnt)

Reboot my edge (bridge mode) router and then reboot the Nighthawk router (usually works but problem comes back after around 10 days). mKAes me think that the Nighthawk to Mikrotik connectivity is somehow killing the DHCP service on the nighthawk.

Even setting to the Nighthawk to AP mode and back to Standard doesnt resolve it without resetting the edge router

Even when disconnected from the internet I can still manage the Nighthawk.

My network config is complex (ish)

Verizon FIOS service (no Verizon router)

Mikrotik Edge Router (bridge Mode) (77.115.17/2**). Internal 192.168.88.1

Nighthawk Router / DHCP internal network hub (10.0.0.1) Address range 10.0.0.2 -10.0.0.150 (static addresses at top of range)

WIFI - Extender and devices

Direct ethernet connect PC

2 Netgear POE 24 port switches

Various attached devices (most with Static IP addresses - home automation system including cameras - mostly running Linux)