fixing the old project errors

controllers/logout.php

@@ -1,7 +1,10 @@
 <?php
+  session_start();
   if(isset($_POST['signout']))
   {
-    $_SESSION["user"] = "";
-	header("Location: ../views/signinPage.php");	
+    session_unset();
+    session_destroy();
+	header("Location: ../views/signinPage.php");
+	exit();
   }
 ?>