ขอถามเรื่องเมื่อกด submit แล้วข้อความในtextarea ที่พิมพ์ไว้ไม่หายไปหน่อยครับ

<td><center><?php echo $objResult["ชื่อฟิลด์รายละเอียด"];?></center></td>

<td><Form action="prefix.php" Method="Post" name="form2" id="form" > <!--ให้ปุ่มsubmit action ไปที่ไหน-->
	
	<script type="text/javascript">
	
		function enable_form(){  //รับค่ามาจากปุ่ม Edits

		x=document.getElementById("JOB_TYPE")
		x.disabled = !x.disabled; //ทำให้สถานะตรงข้าม

		x=document.getElementById("Edit")
		x.disabled = !x.disabled;  //ทำให้สถานะตรงข้าม

		x=document.getElementById("DESCRIPTION")
		x.disabled = !x.disabled;  //ทำให้สถานะตรงข้าม
		}
	</script>


	<Left><Font Size=2><B>แจ้งปัญหาการใช้งาน หรืออื่นๆ</B></Font></Left>

	<Font Size=2><Table Border="0" Bgcolor="#FFFFFF" Face="Ms Sans Serif">
		<Td>เลขที่รับแจ้ง </Td><Td>

			<input readonly type="text" name="REFNO" style="background:#98FB98" value=<?echo $row["REFNO"]?>></Td>
	
		<Td>หมวดปัญหา</Td><Td>
			<Select name="JOB_TYPE_ID" id="JOB_TYPE" size="1"  <?if($row["ID"] != 0){ echo "disabled";}?>> 
				<?php
					$sql="select * from tb_c_job_type";
					$query=mysql_query($sql);
					while($row2=mysql_fetch_assoc($query))
						{
					?>
					<option value="<?echo $row2["ID"]?>" <?if ($row["JOB_TYPE_ID"] == $row2["ID"]){echo "selected";}?>><?echo $row2["JOB_TYPE"]?></option>
					<?
						} 
				?>
			</Select></Td>

 
			<td><Input Type=button  name="mode" value="Edit"  onclick="return enable_form()"  id="Edit" <?if($row["ID"] == 0){ echo "disabled";}?>> </td>	
			<td><Input Type=Submit  name="mode" value="Clear"></td>
			<td><Input Type=Submit  name="mode" value="Save" id="Save"></td>

	<Br>
	<Br>

	<Tr>



		<Td>รายละเอียด</Td><Td>
			<textarea name=DESCRIPTION ID="DESCRIPTION"  style="width: 400px; height: 90px" 
			<?php if($row["ID"] != 0){echo"disabled";}?>><?echo $row["DESCRIPTION"];?></textarea>
	</Tr>
	
	</Table>
	</Font>
			<Input	Type=hidden Name="ID"	id="ID"	value="<?echo $row["ID"];?>"></tr></Td>
</form>

	<Form name="form1" border=1 color="#FF0099" method="post" action="customer.php" enctype="multipart/form-data" id="uplod" >


	<Tr><Td>ไฟล์ที่ 1 :
			<Input Type="file" name="filUpload[]" value="เลือกไฟล์"><input type="image" value="submit" name="deleted" src="bin.png" onClick="return confirm('Delete This File?')" <?if ($filUpload == ""){echo "disabled";}?>></Td></Tr>
			<tr><td>
			<label><?echo $row["FILE1_NAME"];?><?if ($upload) {if($before != ""){$before.="<font color=\"Green\"> Upload Success</font>";}}?> <?echo $before; if ($deleted == "submit"){echo "<font color=\"red\"> file deleted</font>";}?><label></tr></td>
	<tr><Td>ไฟล์ที่ 2 :
			<Input Type="file" name="filUpload1[]" value="เลือกไฟล์";><input type="image" value="submit" name="deleted1" src="bin.png" onClick="return confirm('Delete This File?')" <?if ($filUpload1 == ""){echo "disabled";}?>></tr></Td>
			<tr><td>
			<label><?echo $row["FILE2_NAME"];?><?if ($upload) {if($before1 != ""){$before1.="<font color=\"Green\"> Upload Success</font>";}}?> <?echo $before1; if ($deleted1 == "submit"){echo "<font color=\"red\"> file deleted</font>";}?></label><tr></td>
	<tr><Td>ไฟล์ที่ 3 :
			<input Type="file" name="filUpload2[]" value="เลือกไฟล์"><input type="image" value="submit" name="deleted2" src="bin.png" onClick="return confirm('Delete This File?')" <?if ($filUpload2 == ""){echo "disabled";}?>> </tr></Td>
			<tr><td>
			<label><?echo $row["FILE3_NAME"];?><?if ($upload) {if($before2){$before2.="<font color=\"Green\"> Upload Success</font>";}}?> <?echo $before2; if ($deleted2 == "submit"){echo "<font color=\"red\"> file deleted</font>";}?></label></td><tr>

			<td align=left><Input Type=submit value="Upload" name="upload"></td>
	</form>


---------------------------------------------------------------------------------------------------------------------------------------------------------

if ($upload)
{


	for($i=0;$i<count($_FILES["filUpload"]["name"]);$i++)
		{
			if($_FILES["filUpload"]["name"][$i] != "")
			{
				$before = $_FILES["filUpload"]["name"][$i];
				$ext = pathinfo($_FILES["filUpload"]["name"][$i], PATHINFO_EXTENSION);
				$fileName  = date("YmdHis").".".$ext;
					

				if(move_uploaded_file($_FILES["filUpload"]["tmp_name"][$i],"myfile/".$fileName))
				{
				
				session_start();
					
					$_SESSION['fileName'] = $fileName;
					$_SESSION['before'] = $before;
		
					$dbquery = mysql_db_query($dbname,$sql);
			
				}
				sleep(1);
			}
		}
	
	
	for($i=0;$i<count($_FILES["filUpload1"]["name"]);$i++)
		{
			if($_FILES["filUpload1"]["name"][$i] != "")
			{
				$before1 = $_FILES["filUpload1"]["name"][$i];
				$ext1 = pathinfo($_FILES["filUpload1"]["name"][$i], PATHINFO_EXTENSION);
				$fileName1  = date("YmdHis").".".$ext1;
					

				if(move_uploaded_file($_FILES["filUpload1"]["tmp_name"][$i],"myfile/".$fileName1))
				{
				
			
					$_SESSION['fileName1'] = $fileName1;
					$_SESSION['before1'] = $before1;
		
					$dbquery = mysql_db_query($dbname,$sql);
						
				}
				sleep(1);
			}
		}
	
	
	for($i=0;$i<count($_FILES["filUpload2"]["name"]);$i++)
		{
			if($_FILES["filUpload2"]["name"][$i] != "")
			{
				$before2 = $_FILES["filUpload2"]["name"][$i];
				$ext2 = pathinfo($_FILES["filUpload2"]["name"][$i], PATHINFO_EXTENSION);
				$fileName2  = date("YmdHis").".".$ext2;
					

				if(move_uploaded_file($_FILES["filUpload2"]["tmp_name"][$i],"myfile/".$fileName2))
				{		
		
					$_SESSION['fileName2'] = $fileName2;
					$_SESSION['before2'] = $before2;
				session_write_close();
					$dbquery = mysql_db_query($dbname,$sql);
						
				}
				sleep(1);
			}
		}

}

<form method="post" action="customer.php" enctype="multipart/form-data" target="frame_upload">
...
... ข้อมูลตามที่มี
...
</form>
<iframe name="frame_upload" style="display: none"></iframe>
<script>
function return_ajax(param){
   alert( param);
}

<?php
// ทำตามที่เคยทำ
...
...
...
// ตอนจบ
echo <<<HTML
<script>
window.parent.return_ajax( 'upload finish' );
</script>
HTML;