Hello Alonso Mora,
Thanks for reaching out. To assist you further kindly provide the complete URL of the endpoint you are using to retrieve the Bookings Calendar view. Does the Booking Calendar have any customers assigned under the Customers tab of the booking calendar? Does the issue occur with a specific Booking calendar or others as well? Does the endpoint https://graph.microsoft.com/v1.0/solutions/bookingBusinesses/<BookingCalendarEmail>/customers return any results?
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