By default, only users of Author level and above can view Contact Form Redux contact forms. (Users with “edit_posts” capability.) However, only users who are Editors and above can edit or delete contact forms. (Users with “publish_pages” capability.) Only Administrator users can access the Integration and Options pages.
If you want to allow only administrators to access Contact Form Redux admin pages, you can restrict access by adding the following to the wp-config.php file of your site:
Since only administrators have the “manage_options” capability in WordPress, this will restrict access to Contact Form Redux to administrators.
The constant CFREDUX_ADMIN_READ_CAPABILITY determines who can view contact forms, and CFREDUX_ADMIN_READ_WRITE_CAPABILITY determines who can edit and delete contact forms. CFREDUX_ADMIN_READ_WRITE_CAPABILITY should be the same or more strict than CFREDUX_ADMIN_READ_CAPABILITY.
You can set both constants to whatever capabilities you choose. For more information, see WordPress Roles and Capabilities.