Now I got Error
Uncaught exception 'Braintree\Exception\Configuration' with message 'Braintree\Configuration::merchantId needs to be set (or accessToken needs to be passed to Braintree\Gateway).
Question is that if my merchant ID is not how its creating sub merchant because i able to see sub merchant account in my dashboard but i am going to call this method:
$webhookNotification = Braintree\WebhookNotification::parse($sampleNotification['bt_signature'], $sampleNotification['bt_payload']);
it says
Uncaught exception 'Braintree\Exception\Configuration' with message 'Braintree\Configuration::merchantId needs to be set (or accessToken needs to be passed to Braintree\Gateway).