date-to value="+1" and hidden don't work

We are using easy reservation for our web site and we love it. We updated to premium and using version 3.4.

http://www.jeuxaerofun.com/reservation/

Unfortunately, in the form, date-to and hidden fonctions stop working properly.

Date de départ
Quand prendrez-vous votre location?
[date-from style=”width:75px”][hidden date-from-hour 8][hidden date-from-min 0]

Date du retour
Quand le rapporterez-vous?
[date-to value=”+1″ style=”width:75px”][hidden date-to-hour 8]
[hidden date-to-min 0]

How can we fixe?

Thanks

What do you mean with stopped working exactly? As of the data send to server it seems correct. What for a time does it show for the “test” reservation I just made?
Regards