Appointment+ cant make an appointment

I have for each Sevice one Site. I use the follow shortcodes

When the Site is loading I see the calendar and the time slot but I can't make an appointment. The confirmation dosn' show.
Work only when I click "next month", now I can make an appointment.
When I choose the site from the menu is not possible to make an appointment. I can click on a free time but nothing happens.