I can't find original firmware on the internet anywhere tried to see whats causing the crash/reboot with dmesg and logread but they don't show much please help thanks 
forgot to say it's ztb WE2805AC-DISM-D
Seeing as how it is a ZBT router it will have a hardware watchdog that will reboot unless it is reset regularly. They use it to detect Internet loss.
This happens on most of ZBT routers like the WG1608, WG1602, WG827, WE826-Q and others.
Either the firmware has to take care of this or it has to be disabled by adding a jumper to the board.
I thought it was that i tried to install watchcat and luci-app-watchcat you think that will make it work?
it's still rebooting even after installing kmod header for watchdog and watchcat
Some please help me stop this dang router from rebooting