First of all Impressive Customization and Design of your Site using the one of the Most Popular Themes at WordPress History SIMPLIFY.
The issue must be related to your site Specific. If you have any Caching Plugin or Caching System like CloudFlare, you should also Clear/Purge the Cache.
Please find that we have changed the Text in our Test Environment for both the Free and Extended Version of SIMPLIFY and is working without any issue. Your site is running on SIMPLIFY 3.9 when the Latest Version is 5.1: https://wordpress.org/themes/simplify/
You may update your site with the Latest Version of SIMPLIFY.
SIMPLIFY Free Version:
SIMPLIFY Extended Version:
We believe that, the Theme has no issues like you are facing. It is something from the Customization of your site. You may take our Custom Service if you want us to investigate the issue and fix.