PHP - Cannot Make Header Redirect Work When Session Unavaliable.

Hi

Everyone was kind enough to help with my last issue and am now nearly there.

The data actually populates correctly now in my database, however, it will not direct me to my redirect.

I get the error

Warning: Cannot modify header information - headers already sent by (output started at C:\xampp\htdocs\loginsystem\Permnew.php:4) in C:\xampp\htdocs\loginsystem\Permnew.php on line 124

This is the redirect i am trying to do

anyone any ideas?

Thanks

Steve

<?php
 require "header.php";
?>

<main>
  <div class="wrapper-main">

        <div class="welcomelogged">
          <p>Adding A Permanent New Starter<p>                  
        </div>

    <form class="form-addperm" action="" method="post">
		<table id="Tableperm" width="1000px;" border="0">
			<tr>
			<th align="right" scope="row"><label for="select">Week Commencing</label></th>
	        <td><select name="WeekComm">
	        <option value="WC 6th April">WC 6th April</option>
	        <option value="WC 13th April">WC 13th April</option>
	        <option value="WC 20h April">WC 20h April</option>
	        <option value="WC 27h April">WC 27h April</option>
	        </select></td>
			</tr>
			<tr>
	      	<th align="right" scope="row"><label for="StartDate">Start Date</label></th>
	      	<td><input type="date" name="StartDate" placeholder="Start Date"></td>
	      	</tr>
	      	<tr>
			<th align="right" scope="row"><label for="select1">Consultant</label></th>
	        <td><select name="Consultant">
	        <option value="Steven Buntin">Steven Buntin</option>
	        <option value="Sam Ahmed">Sam Ahmed</option>
	        <option value="David Millington">David Millington</option>
	        <option value="Steven Nixon">Steven Nixon</option>
	        <option value="Grahame Walsh">Grahame Walsh</option>
	        <option value="Helal Ahmed">Helal Ahmed</option>
	        </select></td>
			</tr>
			<tr>
	      	<th align="right" scope="row"><label for="FirstName">First Name</label></th>
	      	<td><input type="text" name="FirstName" placeholder="First Name"></td>
	      	</tr>
			<tr>
	      	<th align="right" scope="row"><label for="LastName">Last Name</label></th>
	      	<td><input type="text" name="LastName" placeholder="Last Name"></td>
	      	</tr>
	      	<tr>
	      	<th align="right" scope="row"><label for="ClientName">Client Name</label></th>
	      	<td><input type="text" name="ClientName" placeholder="Client Name"></td>
	      	</tr>
			<th align="right" scope="row"><label for="Position">Position</label></th>
	      	<td><input type="text" name="Position" placeholder="Position"></td>
	      	</tr>
	      	<th align="right" scope="row"><label for="Comments">Comments</label></th>
	      	<td><input type="text" name="Comments" placeholder="Comments"></td>
	      	</tr>
	      	<tr>
	      	<th align="right" scope="row"><label for="Salary">Salary</label></th>
	      	<td><input type="varchar" name="Salary" placeholder="Salary"></td>
	      	</tr>
	      	<tr>
	      	<th align="right" scope="row"><label for="ChargePercentage">Charge Percentage</label></th>
	      	<td><input type="varchar" name="ChargePercentage" placeholder="ChargePercentage"></td>
	      	</tr>
	      	<ty>
	      	<th align="right" scope="row"><label for="GPNotes">GP Notes</label></th>
	      	<td><input type="text" name="GPNotes" placeholder="GPNotes"></td>
	      	</tr>
		</table>
		<button type="submit" name="addstarter">Add Starter</button>
    </form>	  
  </div>
 </main>

<?php

$dBServername = "localhost";
$dBUsername = "root";
$dBPassword = "";
$dBName = "loginsystemtut";

mysqli_report(MYSQLI_REPORT_ERROR|MYSQLI_REPORT_STRICT);


$conn = mysqli_connect($dBServername, $dBUsername, $dBPassword, $dBName);


if (!$conn) {
    die("Connection failed: " . mysqli_connect_error());
}


if (isset($_POST['addstarter'])) {


  $WeekComm = $_POST['WeekComm'];
  $StartDate = $_POST['StartDate'];
  $Consultant = $_POST['Consultant'];
  $FirstName = $_POST['FirstName'];
  $LastName = $_POST['LastName'];
  $ClientName = $_POST['ClientName'];
  $Position = $_POST['Position'];
  $Comments = $_POST['Comments'];
  $Salary = $_POST['Salary'];
  $ChargePercentage = $_POST['ChargePercentage'];
  $GPNotes = $_POST['GPNotes'];

  $sql = ("INSERT INTO permanent (WeekComm, StartDate, Consultant, FirstName, LastName, ClientName, Position, Comments, Salary, ChargePercentage, GpNotes) values (?,?, ?, ?, ?, ?, ?, ?, ?, ?, ?)");

  $stmt = mysqli_stmt_init($conn);

      	if (!mysqli_stmt_prepare($stmt, $sql)) {
          // If there is an error we send the user back to the signup page.
          header("Location: ../signup.php?error=sqlerror");
          exit();
        }
        else {


    	mysqli_stmt_bind_param($stmt,"sssssssssss",$WeekComm,$StartDate,$Consultant,$FirstName,$LastName,$ClientName,$Position,$Comments,$Salary,$ChargePercentage,$GPNotes);
      
      	mysqli_stmt_execute($stmt);
    	}

  header("Location: ../loginsystem/permnew1.php?success");
  exit();
    }
?>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
   <style>
   .error {color: #FF0000;}
   h6
   {
     font-family: bookman old style;
     font-size:20px;
     text-align: center;
     font-weight: normal;
  }
  h5
  {
    font-family: bookman old style;
    font-size:15px;
    text-align: center;
    font-weight: normal;
  }
  </style>
  <?php
  $nameErr = $emailErr = $websiteErr = $categoryErr;
  $name = $email = $comment  = $website = $reset = $category;
     if ($_SERVER["REQUEST_METHOD"] == "POST") {
       if (empty($_POST["name"])) {
         $nameErr = "Name is required";
       } else {
         $name = test_input($_POST["name"]);
         if (!preg_match("/^[a-zA-Z ]*$/",$name)) {
           $nameErr = "Only letters and white space allowed"; 
         }
       }
       
       if (empty($_POST["email"])) {
         $emailErr = "Email is required";
       } else {
         $email = test_input($_POST["email"]);
         if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
           $emailErr = "Invalid email format"; 
         }
       }
         
       if (empty($_POST["website"])) {
         $websiteErr = "URL is required";
       } else {
         $website = test_input($_POST["website"]);
         if (!preg_match("/\b(?:(?:https?|ftp):\/\/|www\.)[-a-z0-9+&@#\/%?=~_|!:,.;]*[-a-z0-9+&@#\/%=~_|]/i",$website)) {
           $websiteErr = "Invalid URL"; 
         }
       }
    
       if (empty($_POST["comment"])) {
         $comment = "";
       } else {
         $comment = test_input($_POST["comment"]);
       }
       if (empty($_POST["category"])) {
         $categoryErr = "Category is required";
       } else {
         $category = test_input($_POST["category"]);
       }
if (!empty($_POST['name']) && !empty($_POST['email']) && !empty($_POST['website']) && !empty($_POST['category'])) {
 $myemail = "links@loadsofads.com";
 $subject = "Link Submission";
 $message = "Your Link Submission form has been submitted by:
 Website Name: $name
 E-mail: $email
 URL: $website
 Category: $category
 Description:
 $comment";
 mail($myemail, $subject, $message);
 header('location:submitthanks.php');
  }}
  function test_input($data) {
     $data = trim($data);
     $data = stripslashes($data);
     $data = htmlspecialchars($data);
     return $data;
  }
?>
  <?php include'header.php'?>
  <h6>Link Submission</h6>
  <h5><p><span class="error">* required field.</span></p>
  <form method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>"> 
     Name Of Site: <input type="text" name="name" value="">
     <span class="error">* <?php echo $nameErr;?></span>
     <br><br>
     E-mail: <input type="text" name="email" value="">
     <span class="error">* <?php echo $emailErr;?></span>
     <br><br>
     URL: <input type="text" name="website" value="">
     <span class="error">* <?php echo $websiteErr;?></span>
     <br><br>
     Description: <textarea name="comment" rows="5" cols="40"></textarea>
     <br><br>
  Category Of Site: <select size="1" name="category"> 
     <option value=""> -- Please select -- </option>    
     <option>Arts</option>     
     <option>Business</option>     
     <option>Computers</option>     
     <option>Games</option>     
     <option>Health</option>     
    <option>Home</option>     
    <option>Kids and Teens</option>     
    <option>News</option>     
    <option>Recreation</option>     
    <option>Reference</option>     
    <option>Science</option>     
    <option>Shopping</option>     
    <option>Society</option>     
    <option>Sports</option>     
    <option>World</option>
   </select><span class="error">* <?php echo $categoryErr;?></span>
    <br><br>
    <input type="submit" name="submit" value="Submit"> <input type="reset" name="reset" value="Reset Form">
 </form>
<?php include'footer.php'?>