Hi,
I think it is your robots.txt file that is causing the issue. At the moment you have the following:
**User-agent: ***
Disallow:
I would recommend updating it to the following:
**User-agent: ***
Allow: /
Moz also has a good post about what else you can include in your robots.txt file for best practices etc. :
https://moz.com/learn/seo/robotstxt
Hope that helps
Thanks