Welcome to the forum Peggy83.
This really depends on what you mean by the "function to edit text" and what you mean by "doesn't work".
In Scribus you can edit text by opening the Story Editor window or by double-clicking the text frame and editing the text directly in the frame. They are very different functions so you need to specify which one you are having trouble with.
As for "doesn't work", you need to say how it's not working.
For instance, if you're using the Story Editor it could be that:
* the menu option is greyed out so you can't get into the editor, or
* a keyboard command doesn't bring the window up, or
* you can open the window but no text is visible, or
* you can open the window but can't change the text within it, or
* you can open the window and change the text but the text remains the same in the frame after you close the window.
The list of possible "faults" could be huge, so please try and be more specific.
In my experience, when Scribus has been used for a prolonged time - more than a couple of hours - it tends to get very slow and some things go so slowly they don't seem to work (specifically context menus). However, this might just be because my machine doesn't have a large memory so I notice it more than other people. If this is the case I'd recommend closing Scribus every now and again just to clear out whatever the problem might be. It's not a fix, just a way round the issue.
P.S. You don't need to add your post in different sections of the forum. One post is enough for people to find it.