Wrong time on the booking overview

Hello, since the time change (summer/winter time), there has been an error on my client’s booking system. On the Booking overview page, the time that is shown is an hour later than the actual booked time, that is also shown when clicking on the individual booking.

Also some of the customers who book experience this wrong booking time displayed in the confirmation email. But it only happens fore some, not all. Can you please help me fix this, it’s very important, since it’s a vital function on the website.

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