Mass mail does not work

I'm trying to use the mass mail feature in Events Booking. When I select the "Send Mails" button, an error returns the following message: "You must provide at least one recipient email address." Does anyone know why this is happening and what I can do to fix the problem?

Thanks!

Hi Corey

The Massmail feature in Events Booking allows you to send emails to registrants of an event. Did you choose an event from event dropdown when you try to send the email ?

Tuan