Variable value null.

Question

I have use this code for change password .Bu i have face null value in data.

<script type="text/javascript">
$(document).ready(function () {
debugger;
$('#EditPasswordBtn').click(function (e) {
e.preventDefault();
var data = {
"newPassword": $("#newPassword").val(),
"confirmPassword": $("#confirmPassword").val()
};
$.ajax({
url: '/Login/ChangePassword',
type: "POST",
data: JSON.stringify(data),
cache: false,
dataType: "json",
contentType: "application/json",
success: function (response) {
},
error: function (error) {
alert.success(error.Message);
}
});
});
});
</script>
try
{
obj_userMaster.UserPassword = changePassword.NewPassword;
}