PayPal API with Laravel - php

Question

I am using a paypal plugin, and and for some reason I can't get paypal to go to my callback url when payment is complete. I have used the same plugin before which worked so it must be something stupid I am doing.
Here's a sample array of the data I am passing into the plugin
Array
(
[sandboxMode] => 1
[successUrl] => http://x.x.x.x/safespacesforkids/rebuild/public/payment/success
[cancelUrl] => http://x.x.x.x/safespacesforkids/rebuild/public/assessment/checkout
[backendUrl] => http://x.x.x.x/safespacesforkids/rebuild/public/payment/pp/316e7c50a117c91b392a013a6e1a22e9a4f97b1e
[merchantAccount] => myemail#domain.com
[language] => EN
[currency] => AUD
[invoice] => 55ca0738e638d
[purpose] => Company Name
[amount] => 180.68
[remark] =>
)
When I copy backendUrl in to my browser and go there myself it processes the order just fine. but paypal won't
My code
public function redirect()
{
//My Basket - Info
$basket = Cart::getBasket();
//Make payment hash
$user = User::find(Auth::id());
$user->hash = sha1(rand().time());
$user->save();
$paypalInfo = array(
'sandboxMode' => true,
'successUrl' => URL::route('payment.success'),
'cancelUrl' => URL::route('assessment.checkout'),
'backendUrl' => URL::route('payment.paypal', $user->hash),
'merchantAccount' => System::first()->paypal_email,
'language' => 'EN',
'currency' => 'AUD',
'invoice' => uniqid(),
'purpose' => 'Safe Spaces for Kids',
'amount' => Helper::price($basket['total']),
'remark' => ''
);
Helper::pr($paypalInfo,1);
$adapter = Gateway::driver('Paypal')->initialize($paypalInfo);
$generated = $adapter->render();
return View::make('payment/redirect', ['form' => $generated]);
}