This simply means that the webserver software on your Webdock server is not aware of the domain you are using to visit the server. For example, if you are viewing your Webdock server with your own domain “mydomain.com” you need to add it to Server Identity (find it in the main Server Menu) and finally run the SSL Certificates tool.
Once you have completed these two steps, adding all the domains you want your webserver to know about, then you will be able to view your website using your own domain in your browser.