Not getting ajax response on the server even with 200 status - php

Question

I have added an ajax call on the blur of input and click on submit button to verify the email exist or not.
Code is simple to just check the existing data and return true false in response.
On local it is working totally fine but on client's server the ajax is not responding as expected. The response status is 200 but nothing in the preview of response on the console of the browser. For more clarity adding the picture.
Ajax code:
jQuery.ajax({
url : "{{ path('sales_account_email_exist') }}",
type : "POST",
cache : false,
data : {email:email_val,user_id:$("#user-id").val()},
success : function(data){
$(".loader").hide();
var obj = $.parseJSON(data);
if(obj===false)
{
$("#duplicate_email_exist").css("display","inline-block");
errorMessage = '<i class="warning sign icon"></i>' + email_val + ' : Email already exists in the system.';
$("#duplicate_email_exist").html(errorMessage);
email_exist_valid = false;
}
else
{
$("#duplicate_email_exist").css("display","none");
$("#duplicate_email_exist").html("");
email_exist_valid = true;
}
}
})
Ajax backend code:
/**
* #Route("/exist-email", name="sales_account_email_exist",methods={"GET","POST"})
*/
public function emailExist(Request $request): Response
{
$email = $request->get('email');
$user_id = $request->get('user_id');
if (isset($email) && !empty($email)) {
if (isset($user_id) && !empty($user_id)) {
$query = $this->em->createQueryBuilder()
->select('u.id', 'u.email')
->from('App\Entity\User', 'u')
->andWhere('u.email =\'' . str_replace("'", '', $email) . '\'')
->andWhere('u.id !=' . $user_id)
->getQuery();
} else {
$query = $this->em->createQueryBuilder()
->select('u.id', 'u.email')
->from('App\Entity\User', 'u')
->where('u.email = :email')
->setParameter('email', $email)
->getQuery();
}
$email_exist = $query->getArrayResult();
if (!empty($email_exist)) {
return new response('false');
} else {
return new response('true');
}
}
return new response('true');
}

Answer 1

jQuery.ajax({
url : "{{ path('sales_account_email_exist') }}",
type : "POST",
cache : false,
data : {email:email_val,user_id:$("#user-id").val()},
success : function(data){
$(".loader").hide();
var obj = $.parseJSON(data);
if(obj===false)
{
$("#duplicate_email_exist").css("display","inline-block");
errorMessage = '<i class="warning sign icon"></i>' + email_val + ' : Email already exists in the system.';
$("#duplicate_email_exist").html(errorMessage);
email_exist_valid = false;
}
else
{
$("#duplicate_email_exist").css("display","none");
$("#duplicate_email_exist").html("");
email_exist_valid = true;
}
},
// add this
error: function (request, status, error) {
alert(request.responseText); // <-- your code will be here
}
})
Check logs
Add error: statement after success:, probably this will help to find problem.