calendar showing garbage :-)

i have installed this buit the calender is not displaying actual booked slots, and does not correspond with the booking calendar in the backend.

example 25/01/2021 has 1 booking from 18-21, but he calender is showing one green slot from 15-16 with the bookable product name, and 16-17 it shows one booked product with the text 00:00 – 01:00 ‘product name (BOOKED)’
rest of the calendar is empty although there are future bookings.

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