Do you have a coax connected to it?
Did you try it with it disconnected?
Also check the power supply, I’ve seen the wrong supply used before
Have tried it with coax and router cables connected and unconnected . Power supply the correct one, has been working for 2 years with it and i verified voltage output correct with a VOM
Might be a brick.
Can the ISP see it connected?
Potentially they could reprovision it if so. If something is corrupt in it that might over write it.
Otherwise you’re pretty limited if it doesn’t factory reset and you can’t access it.