Dynamic content being cached - php

Question

I've found on several pages of my site that content retrieved from the database appears to be being cached.
Example:
I have a page which uses the following query
SELECT c.ID, c.name FROM member_coupons AS m LEFT JOIN coupons as c on c.ID = m.couponID WHERE m.userID = 'ANONYMOUS' ORDER BY c.ID
If I run the query in phpMyAdmin, I get the expected results
On the website it is correct as well.
I then fill out the form on the same page, selecting anything on the drop downs and submit. This brings you to a confirmation screen, with a link back to the original screen.
PhpMyAdmin shows me the expected results.
But the website is still showing both options until I refresh
- before refresh
The javascript that is called by the page on the submit is:
$("#submit").click(function() {
var text = "&coupon=" + $("#coupons").val();
var text = text + "&card1=" + $("#card1").val();
var text = text + "&card2=" + $("#card2").val();
var text = text + "&card3=" + $("#card3").val();
var text = text + "&card4=" + $("#card4").val();
$.get("ajax.php?action=couponSwap" + text, function(data, status) {
$('#content').html(data);
});
});
and the associated function
function couponSwap($pdo, $get, $user) {
$coupon = $get['coupon'];
switch($coupon) {
case "1RNORMAL":
$cards[] = $user->addRandomCard(1, 'normal');
break;
case "2RNORMAL":
$cards[] = $user->addRandomCard(2, 'normal');
break;
case "1RSPECIAL":
$cards[] = $user->addRandomCard(1, 'special');
break;
case "2RSPECIAL":
$cards[] = $user->addRandomCard(2, 'special');
break;
case "1CNORMAL":
$cards[][] = $user->addCard($get['card1']);
break;
case "2CNORMAL":
$cards[][] = $user->addCard($get['card1']);
$cards[][] = $user->addCard($get['card2']);
break;
case "1CSPECIAL":
$cards[][] = $user->addCard($get['card3']);
break;
case "2CSPECIAL":
$cards[][] = $user->addCard($get['card3']);
$cards[][] = $user->addCard($get['card4']);
break;
}
if( count( $cards ) > 0 ){
foreach ($cards as $cardArray) {
foreach ($cardArray as $card) {
echo '<img src="'.$card["card"]->showImage().'" alt="'.$card["card"]->getName().'"/> ';
$names[] = $card["card"]->getName();
$insertIDs[] = $card['ID'];
}
}
$names = (isset($names)) ? implode(", " , $names) : 'ERROR';
$user->addLog(date("Y-m-d"), "Coupon Swap: " . $names, $insertIDs);
}
$sql = "DELETE FROM member_coupons WHERE couponID = :couponID AND userID = :userID LIMIT 1";
$q = $pdo->prepare($sql);
$q->bindValue(':couponID', $coupon);
$q->bindValue(':userID', $user->getID());
$q->execute();
echo '<p>Swap more coupons</p>';
}
Also seeing issues where the site is thinking a user is logged out even when they are logged in.
Cookies are set using
$expire = time() + (7 * 24 * 60 * 60);
setcookie("cardHoarder", $row['ID'], $expire, '/');
Checking if a user is logged in uses the following code
$loggedIn = (isset($_COOKIE['cardHoarder'])) ? '1' : '0';
This is included in the config file which is included on all the php files on the site. Its being treated as though the cookies aren’t set even though I can see them.
Can also see the issue on the following page - link here - If you browse to this page, select the randomiser link in the header, select another link then go back to the randomiser, the same images show
No errors are being reported on the site. Can anyone point me towards what else to look at