JQuery in Dynamics 365 portals to save value on a DateTimePicker

hi

I am trying to save a value on the date on a crm portal below is the code im using

$(document).ready(function(){

var roundTripFormat = "YYYY-MM-DDTHH:mm:ss.0000000\\Z";

var input = $("#AppointmentStartDate");

var date = moment("06/28/2017").utc();

input.val(date.format(roundTripFormat));

input.siblings(".datetimepicker").data("datetimepicker").setValue(date);

});

This code stopped working for what reason i dont know please help