Change host name

Hello,

I want to change host name, and I can find it in web interface, although I did use the admin account.

And when I tried to change with script in path "cd /opt/observium" and then "php rename_device.php 10.0.0.65 server_what_ever" (I use Ubuntu server 20.04 as host)

"NOT renamed. Could not resolve server_what_ever"

With kind regards

P