Resolved Frequently logged out after changing hostname

[MMM]

I am currently using a Plesk (Web Admin SE) on Ubuntu 22.04 x64 vultr platform and have been experiencing some issues since I changed the default full hostname to subdomain.domain.com.au. I can login to the portal with subdomain.domain.com.au with console password. The portal logs me off straight away after I login. I can still login with the IP address on portal 8443 into Plesk portal to make any changes. Could someone assist, please?

Attached two screenshots where I changed the settings.

 

[Peter Debik]

Clearing the browser cache might help.

 

[MMM]

Cleared the cache and restarted the server.
The issue still there.

 

[Peter Debik]

Have you checked Tools & Settings > Security > Session Idle Time > Allow IP address changes during a single session?

 

[MMM]

It is not ticked

 

[Peter Debik]

Have you tried checking the option?

 

[MMM]

It was certificate issue. thank you Peter.