PayPal PHP自适应Paypal IPN通知

I'm currently using https://github.com/paypal/adaptivepayments-sdk-php to try to do a Delayed Chain Payment through Paypal , everything seems to work as intended but i realised the notify url doesn't seem to be triggering after the payment is authorised,hence i can't log the payment transaction details into db if the user doesn't go back to the return url.

$payRequest = new PayRequest(new RequestEnvelope("en_US"), 'PAY_PRIMARY', $this->input->post('cancel_return'), $this->input->post('currency_code'), $receiverList, $this->input->post('return').'?payKey=${payKey}');

$payRequest->ipnNotificationUrl = site_url('ipnlistener');

My ipnlistener currently just inserts a row of dummy data into the database, it seems to be working as intended when i access it manually. Any idea what might be the issue ? or any workarounds i could attempt ?

added payRequest data

string(545)"requestEnvelope.errorLanguage=en_US&actionType=PAY_PRIMARY&cancelUrl=http%3A%2F%2Flocalhost%2Fweb%2Fclient%2Fmakepayment%2Frere¤cyCode=SGD&ipnNotificationUrl=http%3A%2F%2Flocalhost%2Fweb%2Fclient%2Ftesto&receiverList.receiver(0).amount=8934.26&receiverList.receiver(0).email=test%40hotmail.com&receiverList.receiver(0).primary=1&receiverList.receiver(1).amount=7344&receiverList.receiver(1).email=testtest%40hotmail.com&returnUrl=http%3A%2F%2Flocalhost%2Fweb%2Fclient%2Fmakepayment%2Frere%3FpayKey%3D%24%7BpayKey%7D"