If your website is www.yourdomain.com and you are not able to send an email from a form to yourname@yourdomain.com.

This could be a possible fix if you are using cPanel.

Change your remote routing in cPanel to “Remote Mail Exchanger” this might fix the problem.

Location of Email Routing in cPanel:

 

Change Email routing to “Remote Mail Exchanger”

Emails from your domain name should now be sent and received without problems.