<!-- Html employment row -->
<div class="row employment_block">

        <div class="col-md-3">
            <input type="text" name="job_title[]" placeholder="Job title">
        </div>

        <div class="col-md-3">
            <input type="text" name="job_duration[]" placeholder="Duration (i.e. 3 months / 1 year)">
        </div>

        <div class="col-md-3">
            <input type="text" name="job_location[]" placeholder="Country">
        </div>
        <div class="col-md-3 text-center">
        <button href="#" class="able_btn m-0 w-100 disabled" disabled aria-disabled="true" style="opacity:0.5"> remove </button>
        </div>

    </div>


<!-- AJAX on form submit -->
$(document).ready(function(){

$(".account_cv_update_form").submit(function(evt){
evt.preventDefault();

      var formData = new FormData($(this)[0]);
   $.ajax({
       url: 'handlers/cv_update.php',
       type: 'POST',
       data: formData,
       async: false,
       cache:false,
       contentType: false,
       processData: false,
       dataType: "json",
    success: function (response) {

      switch(response.message){
        case 'success': success();
        break;
        case 'error': error();
        break;

      }

    }
  });
return false;
});

});


<!-- PHP handler code / json encoding array-->

$job_title = $_POST['job_title'];
$job_duration = $_POST['job_duration'];
$job_location = $_POST['job_location'];

$json_data = array(
        'job_title' => $job_title,
        'job_location' => $job_location,
        'job_duration' => $job_duration );

$cv_data = json_encode($json_data);

echo json_encode($response);
exit();