Capcha Not Showing In Form

We are using this plugin on this page: https://achildgrows.com/advertise/

If a user is logged in, they are able to see the characters in the Captcha. If a user is not logged in, which is the case for all who would use this form, they cannot see the characters in the Captcha. We tried changing the settings from “Use global settings” to “Enabled for this form” to no avail. Is there something I’m missing or need to change for this to work?

WP Version 4.4.1
Plugin Version 2.6.7

Thanks in advance.

https://www.ads-software.com/plugins/salesforce-wordpress-to-lead/