Plugin frequently logging me out automatically

The problem I have is that the plugin frequently logs me out, even though I’m the administrator, and it does this while I’m actually working on the site. There is no warning, and I won’t know it’s happened until I try to save something, and I’m told I need to log in first. However, I can’t log back in until I completely sign out of WordPress, and then sign back into everything from scratch.

The biggest issue with this is that I lose work: when the page refreshes to tell me I’m now logged out, I lose everything I’ve just been working on, as going back to the previous page does not work (all my work on that page has cleared). I don’t even get a chance to save a draft version.

Is there any way to stop the plugin logging out the administrator? Is there a timer setting in the plugin I’m not aware of? Or is this possibly a browser cookie issue? (Firefox). However, before now I’ve had to clear all the WordPress cookies to get back into the site when this happens, so I don’t think the browser is clearing any session cookies without my knowledge.

Any pointers welcome, thanks.