รบกวนใครว่างช่วยดูให้ทีครับ session ลำดับแรกไม่มีข้อมูล

print_r($_SESSION);

<?include "header.php";?>
<?php
if($_POST["pro"] !=""){
		 $_SESSION["Line"] = $_SESSION["Line"] + 1;
		 $NewLine = $_SESSION["Line"];
		 $_SESSION["pro"][$NewLine] = $_POST["pro"];	 

}
		 print_r($_SESSION);
?>


<form action="" method="post">
<input name="pro" type="text">
<input type="submit" name="submit" value="Add">
</form>

<table>
<tr>
<th>ลำดับที่</th>
<th>รายการ</th>
</tr>

<?php
if($_POST["pro"] !=""){
$No = 0;
 for($i=0;$i<=(int)$_SESSION["Line"];$i++){
$No++;
?>
<tr>
<td><?php echo $No;?></td>
<td><?php echo $_SESSION["pro"][$i];?></td>
</tr>
<?
 }
  }
?>
<?include "footer.php";?>

<?include "header.php";?>
<?php
if($_POST["pro"] !=""){
		 $_SESSION["Line"] = $_SESSION["Line"] + 1;
		 $NewLine = $_SESSION["Line"];
		 $_SESSION["pro"][$NewLine] = $_POST["pro"];	 

}
		 print_r($_SESSION);
?>


<form action="" method="post">
<input name="pro" type="text">
<input type="submit" name="submit" value="Add">
</form>

<table>
<tr>
<th>ลำดับที่</th>
<th>รายการ</th>
</tr>

<?php
if($_POST["pro"] !=""){
$No = 0;
 for($i=0;$i<=(int)$_SESSION["Line"];$i++){

if(!empty($_SESSION["pro"][$i])){ 
   $No++;
?>
<tr>
<td><?php echo $No;?></td>
<td><?php echo $_SESSION["pro"][$i];?></td>
</tr>
<?
 }
}
  }
?>
<?include "footer.php";?>