Can't login to router unless reset to factory each time

AC1750 WiFi Cable Modem Router

Model C6300 Firmware V2.01.18

MacOS 10.15.6

Home Enviroment

ISP connects directly to CyberPower 1350PFCLCD UPS then to Cable Modem Router

Mac connected via CAT5E

I've had problems logging into this router for a year now to make any configuration changes. I have to factory reset the router in order to log into the router. With 25+ SmartHome devices connected, factory resetting really sucks.

Now I have the need to make minor config changes and cant login unless I reset to factory.

Lately I've noticed the router boots me off and reboots on its own.

I use 192.168.0.1 to login to the router, the home splash screen doesn't load, not in Basic or Advanced.

I can see Logs, Event Logs, Guest Network & other tabs but not, Home, Cable Connection, Wireless, Attached Devices in Basic or Advanced.

It allows me to change the password 

In the last 2 days I've gotton a message when trying to make a config change about another user logged in, I'll attach a ScreenShots PDF 

Any help would be amazing

I'm going out of my mind

D