Q:

update the value of select box with php mysql jquery ajax

I'm facing major issue in changing status in <select> tag to database through jquery-ajax.
Note : I have searched in stackoverflow for this question. but those answere not come close to my question. Here are those links below
link1, link2, link3
When i click on first  row select box the data is sent through ajax and the status column in table get  updated and also it is updated in mysql database.
But when is select 2nd, 3rd row it  doesn't change  not update  the status column in html page nor in database here is the output image.

Thank you in advance..
Here is the details of my code
database table name: ajaxselect

HTML file: index.php
 <?php
    include('processing.php');
    $newobj = new processing();
?>
<html>
    <head>
        <title>Jquery Ajax select <tag> with PHP Mysql</title>
        <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
    </head>
    <body>
        <table border="1">
            <tr>
                <th>Id</th>
                <th>Product name</th>
                <th>Status</th>
                <th>Action</th>
            </tr>
            <?php echo $newobj->display();?>
        </table>
        <script>
            $(document).ready(function(){
                $("#selectstatus").change(function(){
                    var statusname = $("#selectstatus").val();                  
                    var getid = $("#getid").val();                  
                    $.ajax({
                        type:'POST',
                        url:'ajaxreceiver.php',
                        data:{statusname:statusname,getid
                        :getid},
                        success:function(result){
                            $("#display").html(result);
                        }
                    });
                });
            });
        </script>
    </body>
</html>

Ajax file : ajaxreceiver.php
 <?php
    include('processing.php');
    $newobj = new processing();

    if(isset($_POST['statusname'],$_POST['getid'])){
        $statusid = $_POST['statusname'];
        $id = $_POST['getid'];

        $newobj->getdata($statusid,$id);
    }
?>

PHP class file : processing.php
    <?php
    class processing{
        private $link;

        function __construct(){
            $this->link= new mysqli('localhost','root','','example');
            if(mysqli_connect_errno()){
                die ("connection failed".mysqli_connect_errno());
            }
        }

        function display(){
            $sql = $this->link->stmt_init();
            $id=1;
            if($sql->prepare("SELECT id,productname,status FROM ajaxselect")){
                $sql->bind_result($id,$productname,$status);
                if($sql->execute()){
                    while($sql->fetch()){   
            ?>
                        <tr>
                            <td><input type="hidden" id="getid" value="<?php echo $id;?>"><?php echo $id;?></td>
                            <td><?php echo $productname;?></td>
                            <td><p id="display"><?php echo $status;?></p></td>
                            <td>
                                <select id="selectstatus">
                                    <option>Pending</option>
                                    <option>Delivered</option>
                                    <option>Cancelled</option>
                                    <option>Amount Paid</option>    
                                </select>
                            </td>
                        </tr>
            <?php   
                    }
                }
            }
        }

        function getdata($statusid,$id){
            $sql = $this->link->stmt_init();
            if($sql->prepare("UPDATE ajaxselect SET status=? WHERE id=?")){
                $sql->bind_param('si',$statusid,$id);
                if($sql->execute()){
                    echo $statusid;
                }
                else
                {
                    echo "Update Failed";
                }
            }
        }
    }
?>

A:

All of your select-boxes have the same id, so $("#selectstatus").val() will return always the same value. You should get value of changed element. Javascript: this.value or jQuery $(this).val()
Example (notice that selectstatus is a class, so you should add a new class):
HTML
<tr>
    <td><?php echo $productname;?></td>
    <td><p id="display"><?php echo $status;?></p></td>
     <td>
         <select status-id="<?php echo $id;?>" class="selectstatus" id="selectstatus">
            <option value="Pending">Pending</option>
            <option value="Delivered">Delivered</option>
            <option value="Cancelled">Cancelled</option>
            <option value="Amount paid">Amount Paid</option>    
         </select>
     </td>
   </tr>

JS
$(".selectstatus").change(function(){
     var statusname = $(this).val();                  
     var getid = $(this).attr("status-id");                  
                $.ajax({
                    type:'POST',
                    url:'ajaxreceiver.php',
                    data:{statusname:statusname,getid
                    :getid},
                    success:function(result){
                        $("#display").html(result);
                    }
                });
            });

