What information have you tried to add that is not showing up, Lois? Knowing that might help us help you.
The only way to save information as you add it is from the edit pages, and there are 'save' buttons on them which must be clicked. Sometimes when I'm entering information, I am distracted or called away from my computer, or take more time than usual to research or verify the information I"m entering, and my login expires. Usually when this happens and I click 'Save' I am prompted to log in again.
On a related note, the GTG forums can be very helpful when you have any question about WikiTree, but sometimes it takes a little time - especially during holidays. It's important to be logged in to WikiTree when you post here though, so that you can be responded to directly, and so that you are notified when someone commens or answers your query. Hang in there, we'll get it figured out!