Problem with booking

Hi,

Could you please look at my site : http://www.wesele2012.com.pl/adam/?page_id=666 and try to book 21 Grudzien 2012 (21’th December) 12:00 pm. As you can see the slot of time is green(free, “termin wolny”:wink:. This time slot has been booked and confirmed previously. If you try to confirm this appointment( “kliknij w celu potwierdzenia wizyty”:wink:, you’ll receive alert that this slot time is busy (“Przepraszam…”:wink:. Why this time slot hasn’t been filled with correct color previously(busy was customized as red like in legend) ?

Tested with Chrome, Mozilla, IE 8. WordPress 3.4.2.

Regards ,

Jakub