window open does not work after form submit - php

Question

I have the following function to commit the values to a mysql database. The php ajax call works fine. But after the insert function, it does not execute the code related to window.open where it should go to index.html page.
function sendval(){
var tosubmit = validateForm();
if(tosubmit){
showprog();
// now create the json string to insert in the database
var myData = {};
myData.EmpName=localStorage.getItem("username");
myData.LeaveType = $( "#leavetype option:selected" ).text();
myData.LeaveStart = $('#txtFromDate').val();
myData.LeaveEnd = $('#txtToDate').val();
myData.ContactNum = $('#contactnum').val();
myData.Comments = $('#Comments').val();
myData.UsrMail = localStorage.getItem("usermail");
myData.SupMail = localStorage.getItem("supmail");
myData.Status = 'Submit';
var myjson = JSON.stringify(myData);
$.ajaxSetup( { "async": false } );
$.ajax({
method: "POST",
url: "submitleave.php",
data: {"points": myjson}
})
.done(function( msg ) {
if(msg == 'Success') {
alert("Submission successful");
} else {
alert("Could not sumbit - try again");
}
$.ajaxSetup( { "async": true } );
window.open("index.html","_self");
});
} else {
alert("Please enter valid values before submitting the form");
}
}
I tried a few iterations but do not seem to get the error.
Some of the other functions do not work as well.
<header>XXXXX<br>
<br><input type="button" value="Logoff" id="logoff">
</header>
$('#logoff').click(function(){
localStorage.clear();
window.open("index.html","_self");
});
Regards,