It is not advised to edit the designs yourself and you could break parts of your site. If you need something edited you can contact me below.

Make sure you have watched all elementor videos in the learning section.

To edit the styling of the pages you will need to go to the Wordpress dashboard (Wordpress CMS button is located at the bottom left hand corner).

-You must edit with Elementor. 
-Make sure not to edit individual posts that are styled by Theme builder. Check the theme builder first to see which post types and pages are styled. 

The most likely cause is there is a required field that isn’t filled. Required fields are denoted by an Asterisk *. If this doesn’t solve the issue please report it below.