Still having problems with navigation menu

When I switch views from desktop to tablet to mobile, I lose the previous settings for navigation bar in desktop. The latest time- happened this morning when I upgraded to 2.5.2. A couple of weeks ago, the menu disappeared because the fonts switched back to white against white background- nothing I selected. Now something else seems to be the problem. I’ve tried quitting and restarting the app, switching menu to none and then back to primary.

It reverts back to hamburger for all three views and any attempt to revert selection for desktop doesn’t work. I’ve been working on this new site for over a week now and not having problems with other elements, but the only way i can get the desktop navigation back is to delete the whole thing and start over. Clearly not a permanent solution as it takes too much time to recreate all the links and drop downs.

How to fix this? Thank you.