PayPal payout error: Cannot read properties of undefined (reading 'senderFees')

[Betree]

Reported in https://opencollective.slack.com/archives/C0429NTTABF/p1679304696758789 (private)

It looks like PayPal made yet another breaking change to their API:

In some cases, createPaymentResponse.defaultFundingPlan looks like it's not set.

Impacted expense: https://opencollective.com/siduction-eu/expenses/129072. The PayPal response looks like:

{
  "createPaymentResponse": {
    "responseEnvelope": {
      "timestamp": "2023-03-20T02:23:22.144-07:00",
      "ack": "Success",
      "correlationId": "[OBFUSCATED]",
      "build": "[OBFUSCATED]"
    },
    "payKey": "[OBFUSCATED]",
    "paymentExecStatus": "CREATED",
    "httpStatusCode": 200,
    "paymentApprovalUrl": "https://www.paypal.com/cgi-bin/webscr?cmd=_ap-payment&paykey=[OBFUSCATED]"
  },
  "executePaymentResponse": {
    "responseEnvelope": {
      "timestamp": "2023-03-20T02:23:27.815-07:00",
      "ack": "Success",
      "correlationId": "[OBFUSCATED]",
      "build": "[OBFUSCATED]"
    },
    "paymentExecStatus": "COMPLETED",
    "httpStatusCode": 200
  }
}

Looks like we may have to fetch the details from PayPal's API. Note that it doesn't seem to be affecting all expenses, as the admin noted:

ok - i have paid two in the meantime (that went smoothly though): https://opencollective.com/collective-y/expenses/129191, https://opencollective.com/collective-y/expenses/129193

[Betree]

I can now confirm that a payment processor fee was charged on this transaction, PayPal didn't notice us about it in the payload. We'll need to fetch the information from their API.