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Good morning everyone, I love this plugin, but right now it doesn’t work for me. The calendar and reservation on the front as well as on the back.

I can’t book on the back, with the calendar.
When I put the service, this does not recognize and I can not save the reservation.
In front the booking, form does not work when I choose the service, that I make in the system. The system puts the screen blank and a zero

if you go to the website the calendar is at the end

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