The basic reason for this, PHP mail function not working from your server. Please ask your hosting provider to check and enable the PHP mail function for your site.
If the PHP mail function not working you can easily fix it by installing the WP SMTP plugin.
To install the plugin navigate to Plugins > Add New > Search WP SMTP > Install > Active or download it from the website https://wordpress.org/plugins/wp-smtp/
If still not work or you do not understand then send your admin login to our agents support in and explain your issue https://favethemes.zendesk.com/hc/en-us/requests/new.