My PHP, jquery, ajax form submission not working

i have a php form im trying to submit using ajax and its saving data properly but its always returning the error message not the success, any help please to go about it.

$(document).ready(function() {
       var loader='<img src="https://media.giphy.com/media/11ASZtb7vdJagM/giphy.gif" />';
       
	   
	   //if submit button is clicked
     
		$('#submit').click(function () {       
			
			//show the loader
			$('.loading').html(loader).fadeIn();     
		  
			var prog_description = $('input[name=prog_description]').val();
			var type_of_contrib = $('select[name=type_of_contrib]').val();
			var benefit_factor = $('input[name=benefit_factor]').val();
			var budgeted_spend = $('input[name=budgeted_spend]').val();
            var actual_amount = $('input[name=actual_amount]').val();
            var current_status = $('select[name= current_status]').val();
            var anticipated_completion = $('input[name= anticipated_completion]').val();
           
			 
	 
			
			//organize the data properly
            var form_data = 
            
           'prog_description='+prog_description+
			'&type_of_contrib=' +type_of_contrib+
           '&benefit_factor='+benefit_factor+
            '&budgeted_spend='+budgeted_spend+
            '&actual_amount='+actual_amount+
            '¤t_status='+current_status+
            '&anticipated_completion='+anticipated_completion;

			 
			//disabled all the text fields
			$('.text').attr('disabled','true');
			 
			 
			//start the ajax
			$.ajax({
				//this is the php file that processes the data and send mail
				url: "process.php",
				 
				//POST method is used
				type: "POST",
	 
				//pass the data        
				data: form_data,    
				 
				
				//success
				success: function (html) {             
					//if process.php returned 1/true (send mail success)
					if (html===1) {                 
						//hide the form
						$('#fupForm').fadeOut('slow');                
						 
						 
						 //hide the loader
						 $('.loading').fadeOut();   
						 
						//show the success message
						$('.message').html('Successfully Registered ! ').fadeIn('slow');
						 
						 
						 
					//if process.php returned 0/false
					} else alert('Sorry, unexpected error. Please try again later.');              
				}      
			});
			 
			//cancel the submit button default behaviours
			return false;
    });
}); 
 
 
</script>

<?php

session_start();
/* Attempt MySQL server connection. Assuming you are running MySQL
server with default setting (user 'root' with no password) */
$link = mysqli_connect("localhost", "root", "", "socio_economic");

// Check connection
if ($link === false) {
    die("ERROR: Could not connect. " . mysqli_connect_error());
}


// Prepare an insert statement
$sql = "INSERT INTO socio_spends (prog_description,type_of_contrib,benefit_factor,budgeted_spend,actual_amount,current_status,anticipated_completion) VALUES (?, ?, ?,?,?,?,?)";

if ($stmt = mysqli_prepare($link, $sql)) {
    // Bind variables to the prepared statement as parameters
    mysqli_stmt_bind_param($stmt, "sssssss", $prog_description, $type_of_contrib, $benefit_factor, $budgeted_spend, $actual_amount, $current_status, $anticipated_completion);

    // Set parameters
    $prog_description = (isset($_POST['prog_description']) ? $_POST['prog_description'] : '');
    $type_of_contrib = (isset($_POST['type_of_contrib']) ? $_POST['type_of_contrib'] : '');
    $benefit_factor = (isset($_POST['benefit_factor']) ? $_POST['benefit_factor'] : '');
    $budgeted_spend = (isset($_POST['budgeted_spend']) ? $_POST['budgeted_spend'] : '');
    $actual_amount = (isset($_POST['actual_amount']) ? $_POST['actual_amount'] : '');
    $current_status = (isset($_POST['current_status']) ? $_POST['current_status'] : '');
    $anticipated_completion = (isset($_POST['anticipated_completion']) ? $_POST['anticipated_completion'] : '');

 
    

    // Attempt to execute the prepared statement
    if (mysqli_stmt_execute($stmt)) {
        
        echo '1';

        $socio_id =mysqli_insert_id($link);

      $_SESSION['socio_id'] =$socio_id;
        
    } else {
        echo "ERROR: Could not execute query: $sql. " . mysqli_error($link);
    }
} else {
    echo "ERROR: Could not prepare query: $sql. " . mysqli_error($link);
}
  
header('Location:index.php');
// Close statement
mysqli_stmt_close($stmt);

// Close connection
mysqli_close($link);


exit();