Multiple series of time slots on special day display last one

Hi,

I have installed version 4.3.1.

When I add multiple series of time slots to a one special day, only the last series is displayed in the calendar at the frontend

Example:
To a employee I added a special day at January 23th, 1:00-2:00, with a service which takes 15 minutes. This works fine. Four slots are displayed in the booking calendar at the frontend.

If I add at the same date a special day with the same service, at 3:00-4:00. Only these last four slots (series) are displayed.

Regards,

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