insert ไม่ได้อ่ะค่ะ ช่วยดุทีค่ะ ไม่รู้ว่าเกิดจากอะไร รบกวนทีค่ะ

<?
$host="localhost";
$user="mit";
$password="mitdb";
$dbname="mikasa";
$connection=mysql_connect($host,$user,$password)or die("เชื่อมต่อฐานข้อมูลไม่ได้");
mysql_select_db($dbname) or die("ไม่สามารถเลือกฐานข้อมูลได้");
mysql_query("SET NAMES UTF8");

   

$s2="(SELECT Po FROM qc_record ORDER BY LotID DESC LIMIT 0,1)"; 
$s1="(SELECT MAX(Std_value) as Std_value FROM standardvalue)";
$s3 = "(SELECT Balltype  FROM qc_record ORDER BY LotID DESC LIMIT 0,1)";
$q1=mysql_query($s1);
$q2=mysql_query($s2);
$q3 =  mysql_query($s3);
$row2 = mysql_fetch_array($q2);
 $row1 = mysql_fetch_assoc($q1);
$row3 = mysql_fetch_array($q3);
//$max_id=$row1['Std_value']; 
$max =$row2['Po'];
$maxa =$row3['Balltype']; 






mysql_query("ALTER TABLE  claimwork AUTO_INCREMENT =1");

$txtpo = $_POST['txtpo'];   
$txtmodel = $_POST['txtmodel'];       


$id_path=$_GET["edit_id"];
$id_path1=$_GET["edit"];

$str = "INSERT INTO  claimwork ";
$str .="(ID,Balltype,Datechk,Hour,Numball,Pass,NG,Edit,Numclaim,ch1,ch2,ch3,ch4,ch5,ch6,ch7,ch8,ch8.1,ch9,ch10,ch11,ch12,ch12.1,Po,CountryID)";
$str .="VALUES";
$str .="('".$s."','".$txtmodel."','".$_POST["dateupdate"]."','".$_POST["txthour"]."','".$_POST["txtball"]."','".$_POST["txtpass"]."','".$_POST["txtng"]."','".$_POST["txtedit"]."','".$_POST["txtbillclaim"]."','".$_POST["CheckboxGroup1"]."'";
$str .=",'".$_POST["CheckboxGroup2"]."','".$_POST["CheckboxGroup3"]."','".$_POST["CheckboxGroup4"]."','".$_POST["CheckboxGroup5"]."','".$_POST["CheckboxGroup6"]."'";
$str .= ",'".$_POST["CheckboxGroup7"]."','".$_POST["CheckboxGroup8"]."','".$_POST["CheckboxGroup1_2"]."','".$_POST["CheckboxGroup9"]."','".$_POST["CheckboxGroup10"]."','".$_POST["CheckboxGroup11"]."','".$_POST["CheckboxGroup12"]."','".$_POST["CheckboxGroup1_3"]."'";
$str .=",'".$txtpo."','".$_POST["txtcity"]."')";
//$str .= "WHERE  Po = '$id_path' AND Balltype = '$id_path1'";

$query = mysql_query($str);

if ($query){

echo" บันทึกเรียบร้อย <script>window.location.href='bill.php?edit_id=$id_path&edit=$id_path1' ;</script>";
	exit(); 
}

?>