An Admin is logged out automatically after 30 minutes.
This cannot be changed, for security reasons.
If you get logged out right after you've logged in, one possible cause is that you’ve managed to log in to an older release version of LeadDesk. You can see the version you’re logged into in the address bar, so for example in this url:
"r78.14" is the version that you are using.
Normally these old versions get pruned automatically, but sometimes the URL is stored in cookies and can still be accessed by your browser, especially if you use bookmarks to access the login page. If you have the login page bookmarked, please edit the URL to https://login.leaddesk.com/ (so without the version). What this does is, it always redirects to the latest release version of LeadDesk. This way, you can continue using the bookmark as normal, but always ensure that you’re on the latest version.
Another possible cause can be the timeout time set in the campaign settings. This setting is campaign specific, so check which campaign you were calling in at the moment you got logged out, and check the timeout setting for that campaign from the campaign settings (see Agent session timeout).