I can't access the UI page

I can’t access the UI page with 404 error. How can I fix this, updating the firmware without dashboard? SSH is enabled.

I tried,
1.I have pinged mybook, destination host unreachable.
2.Reset button doesn’t work,
3.Reboot mbl and router doesn’t work,

Does your router see the device? If you swap the Ethernet cables connecting rout MBL and your computer to your router, is there still communication between your router and computer? (In other words, it the cable good?) Have you made any changes to your router’s DHCP settings? Have you made any changes to the firewall on either your computer or router? (I know these are possibly insulting “Is it plugged in?” kind of questions but sometimes it’s worth asking?)

Do you have anything else on your LAN? If so, is everything else working? (It could be a router problem rather than a MBL problem.)

my router doesn’t see device. I did not make any changes. I just changed the location of the router. I may have shook the mbl.