Cannot get invoice in respose of CreateRecurringPaymentsProfile in paypal - paypal

Question

My intention is to create a Recurring Profile and pass a company_id as custom parameter to be stored IPN database, where I can create a relation between payment and for which company it was done.
I have read that while creating Recurring Payment Profile to get some custom value in IPN database, you should pass it in PROFILEREFERENCE parameter and then retrieve it from rp_invoice_id in response.
I cannot get the desired output
My request:
$inputData = array(
'METHOD' => 'CreateRecurringPaymentsProfile',
'TOKEN' => $_GET['token'], //get from GetExpressCheckout
'PAYERID' => $billerInfo['PAYERID'], //from GetExpressCheckout response
'PROFILESTARTDATE' => date("Y-m-d h:i:s", strtotime("+5 seconds")), //2012-05-11T00:00:00Z #Billing date start, in UTC/GMT format
'DESC' => 'LeaveBuddy: subscription amount is $' . $bill .' for the provided service ($12 per user per year).', //#Profile description - same as billing agreement description
'BILLINGPERIOD' => 'Year', #Period of time between billings
'BILLINGFREQUENCY' => 1,#Frequency of charges
'AMT' => 10, //Todo: dynamically calculate the amt #The amount the buyer will pay in a payment period
'CURRENCYCODE' => 'USD',#The currency, e.g. US dollars
'COUNTRYCODE' => 'US',#The country code, e.g. US
'MAXFAILEDPAYMENTS' => '0',#Maximum failed payments before suspension of the profile
'PROFILEREFERENCE' => 'companyid=1', //my custom value
);
The response that I am getting is:
{"InstantPaymentNotification":{"id":"553db30b-ea1c-4f68-8b5d-4fe5cbdd56cb","notify_version":"3.8","verify_sign":"A--8MSCLabuvN8L.-MHjxC9uypBtAQZom1C7.mbS1Jv-J898ZO0eeOr9","test_ipn":"1","address_city":null,"address_country":null,"address_country_code":null,"address_name":null,"address_state":null,"address_status":null,"address_street":null,"address_zip":null,"first_name":"code","last_name":"booster","payer_business_name":null,"payer_email":"codebooster#gmail.com","payer_id":"XXXXXXXX","payer_status":"verified","contact_phone":null,"residence_country":"US","business":null,"item_name":null,"item_number":null,"quantity":null,"receiver_email":"boom#gmail.com","receiver_id":null,"custom":null,"invoice":null,"memo":null,"option_name1":null,"option_name2":null,"option_selection1":null,"option_selection2":null,"tax":"0.00","auth_id":null,"auth_exp":null,"auth_amount":null,"auth_status":null,"num_cart_items":null,"parent_txn_id":null,"payment_date":null,"payment_status":null,"payment_type":null,"pending_reason":null,"reason_code":null,"remaining_settle":null,"shipping_method":null,"shipping":"0.00","transaction_entity":null,"txn_id":"316859739","txn_type":"recurring_payment","exchange_rate":null,"mc_currency":null,"mc_fee":null,"mc_gross":10,"mc_handling":null,"mc_shipping":null,"payment_fee":null,"payment_gross":null,"settle_amount":null,"settle_currency":null,"auction_buyer_id":null,"auction_closing_date":null,"auction_multi_item":null,"for_auction":null,"subscr_date":null,"subscr_effective":null,"period1":null,"period2":null,"period3":null,"amount1":null,"amount2":null,"amount3":null,"mc_amount1":null,"mc_amount2":null,"mc_amount3":null,"recurring":null,"reattempt":null,"retry_at":null,"recur_times":null,"username":null,"password":null,"subscr_id":null,"case_id":null,"case_type":null,"case_creation_date":null,"created":"2015-04-27 03:54:51","modified":"2015-04-27 03:54:51"},"PaypalItem":[]}
So i cannot find any [rp_invoice_id] parameter here, and my invoice is also appearing null. Can any one tell me what I am missing?