Month and day inverted when saving to database

I am using datepicker of jqueryUI to choose the date in a calendar, the problem is, if I choose 04/12/2017 it is saved in the 12/04/2017 database.

datepicker:

$('#schedulingCalendar').datepicker({
                dateFormat: 'dd/mm/yy',
                beforeShowDay: function(date){
                    var string = jQuery.datepicker.formatDate('d-m-yy', date);
                    return [ $.inArray(string, arrayDaysToshow) >= 0 ]
                },
                onSelect: function(){
                    $('#schedulingCalendar').removeClass('input-validation-error');
                    $('#messageSchedulingDate').hide();
                    $('#messageCheckDate').hide();
                },
                onClose: function(){
                    $("#panelCalendar").animate({'height': '100%'}, 150);
                }
            });

If I change the dateFormat to yy/mm/dd , it saves correctly in the database, remembering that this problem occurs only in production , in debug it works normal .

OBS: debugging the code until the moment of SaveChanges (use repository) the date is correct ( 04/12/2017 ) but when consolidating in the database this 12/04/2017

EDIT another curious thing, I am using ToString("d MMM yyyy") to display the date after saving, so debug displays for example 4 dez 2017 and the server thus displays 4 Dec 2017