Had that issue after applying the patch that incremented Avada version from 5.5.2 to 5.6
Reset all caches to no avail.
After a whole day of disabling plugins one by one and testing, including disabling all custom code section by section I submitted a ticket. Since it’s been several hours and there was still no response, I decided to go in and tinker with theme settings again.
This time around I toggled off and on each of the settings I had changed from default. Nothing happened until I got to the Advanced | Dynamic CSS & JS section. I turned off Load Media-Queries Files Asynchronously, then turned it back on, and hit Save changes.
For some reason, doing that stupid thing worked for me. lol
Give it a try. It might work for you.