Being told you are logged out when you are not.....

Anyone else have that problem....?
I was always told that on the old system after a couple of minutes even though it showed I was still logged in but when I pressed the submit button
it would flash up so you could sign in again without having to go to the top of the page & everything was fine,now that has vanished the only way I can find of signing in again is to log out at the top & back in & obviously then loose the posting,it says refresh & sign in again,refresh what & where is it please,I am a computer ignorant person & haven't had to do that before,have to say at the moment have wasted more time trying to post than succeeding with the new system,also haven't managed to find the members list that we had before so help with that too please,thanks.
Now lets see if I have managed to type this quick enough before it tells me I am not logged in again & need to refresh page & sign in......

I've increased the session time from 15 minutes to 30 minutes.. That should be plenty for people to complete editing a post before submitting.