confirmation message delays

Hi, I have this site working with contact form 7 and your plugin. The emails send perfectly, but the confirmation message takes a long time to appear (to much), so the user don´t know if the message was sent and click a lot of times the SEND button.

Could there be a problem or conflict between this plugin and contact form 7 that makes the message take so long to appear?

Thanks for your support
Regards

The page I need help with: [log in to see the link]