Hi,
Can you confirm that you are fully updated? (Theme and Plugins)
The latest version numbers as of this time are: (http://theme.co/changelog/) Then you can compare them to what’s installed on your site.
X Theme 4.4.1
Cornerstone 1.2.3
If you find anything to be out of date, you can review our update guide.
After that please check the link below for your guide in validating your site – https://community.theme.co/kb/product-validation/
Hope that helps.