This is normally a cache issue or plugin conflict. But most of the cache.
Try this process.
Step 1. Elementor - Tools - Regenerate CSS and files and Sync library
Step 2. Clear / Purge any caches that you might be using, including plugins, server/hosting caches and DNS caches such as cloudflare.
Step 3. Open the page you've been having problems with the edit, once its opened. Press control F5 on your keyboard to do a hard browser refresh.
If the problem is still there, It might also be worth clearing your browser caches too, but not often needed.
If the problem then continues, its nearly certain that its a plugin conflict, best way to diagnose these is to slowly disable plugins and refreshing the page until it is fixed. Normally its a plugin, or script which is using that specific page, for example if you've got a 3rd party elementor widget plugin and have used a widget on the page, its likely it will be that.