รบกวนช่วยดูคำสั่ั่ง update ไม่เพิ่มเข้าฐานข้อมูลให้หน่อยค่ะ

<?php
require_once ('connect.php');
connect() ;

$sql = "SELECT * FROM stockmaster where Id= " . $_GET["Id"];  
$BrnrecordSet = mysql_query($sql, $objConnect) or die(mysql_error());          
?>

<form name="form1" method="post" action="EditRActual.php">
<?php
while ($Row = mysql_fetch_array($BrnrecordSet))
{
	$BrnId = $Row["BranchId"];
	$ProductCode = $Row["ProductCode"];
	$stocktype = $Row["stocktype"];
	$SerialNo = $Row["SerialNo"];
	$Spec= $Row["Spec"];
    $ActualQTY = $Row["ActualQTY"];
	$Status = $Row["Status"];
	$Statusdate = $Row["StatusDate"];
	
}
?> 
<table border="0" cellspacing="0" cellpadding="5" width="80%" align="center">
	<tr>
    	<td colspan="2" bgcolor="#0000FF" height="25" align="center"><font color="#FF0000">แก้ไขข้อมูลแผนการผลิตรถโชว์</font></td>
    </tr>
    <tr>
    	<td width="36%" align="right" valign="top">สาขา:</td>
        <td width="64%">
          <input type="hidden"  name = "Id" value="<?php echo $_GET["BranchId"]; ?>" />
        <input type="text" name="BranchName" value="<?php echo $BrnId; ?>">
        </td>
    </tr>
    <tr>
    	<td width="36%" align="right" valign="top">รุ่นรถ</td>
        <td width="64%">
         <input type="text" name="ProductCode" value="<?php echo $ProductCode; ?>">
          </td>
    </tr> 
    <tr>
    	<td width="36%" align="right" valign="top">เลือกสต๊อก</td>
        <td width="64%">
        <select name="stocktype" id="stocktype" />
          <option >กรุณาเลือกสต๊อก</option>
          <option value="S" >S</option>
          <option value="R">R</option>
          </select>
          </td>
    </tr> 
    <tr>
    	<td width="36%" align="right" valign="top">Serial No:</td>
        <td width="64%">
         <input type="text" name="SerialNo" value="<?php echo $SerialNo; ?>">
          </td>
    </tr> 
    <tr>
    	<td width="36%" align="right" valign="top">รายละเอียดรถ</td>
        <td width="64%">
         <input type="text" name="Spec" value="<?php echo $Spec; ?>">
          </td>
    </tr> 
    <tr>
    	<td width="36%" align="right" valign="top">จำนวนที่ผลิต</td>
        <td width="64%">
         <input type="text" name="QTY" value="<?php echo $ActualQTY; ?>">
          </td>
    </tr> 
     <tr>
    	<td width="36%" align="right" valign="top">สถานะรถ</td>
        <td width="64%">
         <input type="text" name="Status" value="<?php echo $Status; ?>">
          </td>
    </tr> 
     <tr>
    	<td width="36%" align="right" valign="top">วันที่</td>
        <td width="64%">
         <input type="text" name="Statusdate" value="<?php echo $Statusdate; ?>">
          </td>
    </tr> 
     <tr>
    	<td width="36%" align="right" valign="top"></td>
        <td width="64%">
        <input type="submit" name="submit" value="บันทึก">
        <a href="stockplanlist.php" role="button">กลับ</a>
          </td>
    </tr> 
    
    	
        	
      	</td>
        </tr>
</table> 

</form>