Hi,
Please, note that this might be a problem related to the hosting configurations of your website. Please install WP SMTP plugin and go to Settings > WP SMTP page. Scroll down to the bottom and send a test mail to your email address.
If the test email will be sent, then the issue is triggered by Form Maker plugin, and we will need to have a closer look.
But in case the test mail fails, the problem is on the server of your website. Please contact your hosting provider in this case, and ask them to enable mail functions on your site.
Thanks! Have a great day!