This one is weird and might suggest an underlying problem in the code. Somehow, a one-time donation became recurring between the form submission and us making API calls to Adyen.

In the logs, I see the following (recurring is empty):

Nov  9 09:15:21 payments1007 adyen_gateway: 195292613:195292613.1 Redirecting for transaction: {
    "gateway_txn_id": false,
    "response": false,
    "gateway_account": "WikimediaDonations",
    "fee": 0,
    "contribution_tracking_id": "195292613",
    "utm_source": "Waystogive.default~default~default~default~control.cc",
    "utm_medium": "Waystogive",
    "utm_campaign": "C11_Waystogive",
    "language": "en",
    "email": "k*********@gmail.com",
    "first_name": "K*********",
    "last_name": "H*********",
    "street_address": "7*********",
    "country": "US",
    "postal_code": "*********",
    "gateway": "adyen",
    "order_id": "195292613.1",
    "recurring": "",
    "payment_method": "cc",
    "payment_submethod": "",
    "currency": "USD",
    "gross": "2.75",
    "user_ip": "*********",
    "date": 1699521321
}

but then further, we get recurring-specific exceptions such as

Nov  9 09:15:22 payments1007 SmashPig-Adyen: adyen::195292613:195292613.1  | paymentResult element missing from Adyen createPayment response. | false | 

This is thrown in \SmashPig\PaymentProviders\Adyen\CardPaymentProvider::createRecurringPaymentFromToken()  here

Nov  9 09:15:22 payments1007 SmashPig-Adyen: adyen::195292613:195292613.1  | SOAP authorise request threw exception! | 

This is thrown in \SmashPig\PaymentProviders\Adyen\Api::createPayment() here, which is only called within a recurring flow. 

One explanation could be that Adyen did not send over the usual $params['encrypted_payment_data'] data, which would then cause a donation to be treated as recurring.

The donation is also suspicious, the amount and hit count, 6 attempts from the origin IP, stand out.

Happy hunting!