When retrieving all reservations, if there is no date filter all the bookings that are 7 days in the past will be returned by default.
In order to retrieve reservations for a specific date, you will need to filter by startDate and set it to the arrival date. If there is no endDate specified within the API query, then all the bookings from the startDate will be returned. The API response will then need to be manually filtered in order to only return the bookings for a specific date.