Bookings calendar shortcode not working

Hello,
I inserted the shortcode [salon_booking_calendar] in a page so that users could see (before using the booking form) the days and hours available for booking.
The shortcode displays a calendar with a column for each assistant, but no booking is visible though bookings were done for the period of time and are visible in the back-end.
Is it possible to fix this problem ?
Best regards,
Pierre Vassort

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