PLugin not working properly

the booking calender appears correctly and the form looks great but all of a sudden when someone books they Thanks message appears but no emails are sent to the booker or the admin
if i go to the admin panel and try to add a reservation manually i get the same thanks message but no emails are sent and the calendar still shows as available and no pending reservatios are shown in the control panel

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