Not able to create funding saurce token

I am trying to use php code given in documentation for creating funding saurce in my sandbox account
and I am getting this error ==>Call to undefined method DwollaSwagger\CustomersApi::getCustomerCardToken()

Hi @Netset_PHP_Team – ah, looks like we’ve yet to include that function in the swagger generated PHP SDK. Sorry about that, and thanks for reporting! We’ll get that updated soon!

In the meantime, please continue generating the card-token via our Postman collection, or via cURL or some other HTTP client, like Guzzle.