On my Forum at https://www.bushverse.com/bushoz1/ the Register and Login links have disappeared from the top menu. I have deleted the menu and resaved it in the Menus area. It uses the WP Foro Shortcodes for the links to the menus.
If you go to a category however in the Forum, the Register and Login links appear in the menu. Very weird.
This is something very strange, it's almost impossible to say what have you done incorrectly that affected only these two menus. Please go to Dashboard > Appearance > Menus admin page, edit the wpForo Navigation Menu, open the Login and Register menus (settings) and take a screenshot.
Also, please provide a full list of plugins in a txt file by coping site info in Dashboard > Tools > Site Health > Site Info Tab.
Also there are some issues in this site:
Thank you for your response.
Requested items are attached.