ช่วยเขียน for loop update ให้ทีครับ ตัวที่เขียนไว้มันจะเอา ข้อมูล id 6 มา update ข้อมูล id ตัวอื่นครับ

					<?php
						$strSQL = "SELECT * FROM tbl_mat_detail1 WHERE id_tbl_mat_detail ='".$_GET["ID"]."' ";	
						$objQuery = mysqli_query($conn,$strSQL);
						
						$i=1;
							while($objResult = mysqli_fetch_array($objQuery))							
							{	
						?>
					<tr>
						<td style="text-align: center;"><?php echo $i;?></td>
						<td><?php echo $objResult["pn"];?></td>
						<td><?php echo $objResult["mat_desc"];?></td>					
						<td><input type="text" name="qty[]" value="<?php echo $objResult["qty"];?>" onKeyUp="CheckNum(this,event);" required></td>
						<td><input type="text" name="invoice[]" value="<?php echo $objResult["invoice"];?>" required></td>
						<td><input type="text" name="remark[]" value="<?php echo $objResult["remark"];?>" required></td>
						<?php
							$i=$i+1;
							}
							
						?>
					</tr>

<?php	

	$serverName="localhost";
	$userName="root";
	$userPassword="123456";
	$dbName="dragster";

	$conn=mysqli_connect($serverName,$userName,$userPassword,$dbName);
	$conn->set_charset("utf8");
	//Find id for edit data 
	$strSQL = "SELECT * FROM tbl_mat_detail1 WHERE id_tbl_mat_detail ='".$_GET["ID"]."' ";	
	$objQuery = mysqli_query($conn,$strSQL);	
	$objResult = mysqli_fetch_array($objQuery);
	
	$myid=$objResult["id"];
	//echo $myid;
	//echo "<br>";
	//end find id

	
	$qty = $_POST[qty];
	$invoice=$_POST[invoice];
	$remark=$_POST[remark];
		
	for ($i=0; $i < count($qty); $i++) {
		
		$strSQL1 = "UPDATE tbl_mat_detail1 SET qty='".$qty[$i]."',invoice = '".$invoice[$i]."', remark = '".$remark[$i]."' WHERE id_tbl_mat_detail  = '".$_GET["ID"]."' and id = $myid+$i ";					
		$objQuery1 = mysqli_query($conn,$strSQL1); 
		//echo $strSQL1;
		//echo "<br>";
	}

	
	$ID_S=$_GET["ID"];
	
	if($objQuery1)
	{		
		echo "<script language=\"javascript\">";
		echo "alert('Edit Data Material Kitting Complete ');";		
		echo "window.location='ShowdataMat_Dragter.php?ID=$ID_S';";
		echo "</script>";
	}else
	{
	echo "Error Save [".$strSQL1."]";
	}
	mysqli_close($conn);
?>