Please update to the most recent version of Pro Theme. I see that you are using Pro version 2.2.1. Please update to Pro version 2.2.3 and see how it goes. Along with that please remove all your customisations.
To update Pro Theme please take a look at following resources:
Version compatibility guide: To learn about the latest and compatible versions of bundled and supported plugins, please take a look at following doc:
2. Theme Update guide: Please take a look at following article to update Cornerstone.
3. Please take a look at following doc about changelog: