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Question

Sessions does not work when I change directory. I mean my files that contain codes for sessions run on the main directory. However, when I upload same files to different directory, they does not run. The same codes, files but not working in different directory. What is the problem? I confused.

Here is my codes:

<?php
    ob_start();
session_start();

  include("db.php");

$rota=strip_tags($_POST["rota"]);

$date=strip_tags($_POST["date"]);

$_SESSION['rota']=$rota;
$_SESSION['date']=$date;

?>
------

<?php session_start();
ob_start();
  include("db.php");
$date=$_SESSION["date"];
$rota=$_SESSION["rota"];
echo "Date :    <b>".$date."<br><br></b>"; 

?>

And here is my error log:

[12-Aug-2016 13:51:41 UTC] PHP Warning:  session_start(): Cannot send session cookie - headers already sent by (output started at /home/karelyac/public_html/reserve/en/y1s3.php:1) in /home/karelyac/public_html/reserve/en/y1s3.php on line 3
[12-Aug-2016 13:51:41 UTC] PHP Warning:  session_start(): Cannot send session cache limiter - headers already sent (output started at /home/karelyac/public_html/reserve/en/y1s3.php:1) in /home/karelyac/public_html/reserve/en/y1s3.php on line 3
[12-Aug-2016 13:51:41 UTC] PHP Deprecated:  mysql_connect(): The mysql extension is deprecated and will be removed in the future: use mysqli or PDO instead in /home/karelyac/public_html/reserve/en/db.php on line 7
[12-Aug-2016 13:51:43 UTC] PHP Warning:  session_start(): Cannot send session cookie - headers already sent by (output started at /home/karelyac/public_html/reserve/en/y1s2.php:1) in /home/karelyac/public_html/reserve/en/y1s2.php on line 3
[12-Aug-2016 13:51:43 UTC] PHP Warning:  session_start(): Cannot send session cache limiter - headers already sent (output started at /home/karelyac/public_html/reserve/en/y1s2.php:1) in /home/karelyac/public_html/reserve/en/y1s2.php on line 3