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I'm currently trying to complete a test payment on a Quickpay integration. I successfully generate a redirect url via the API like so,

POST https://api.quickpay.net/payments

BODY

{
    "order_id": "A4asdB2343", // This is generated at random each request
    "currency": "EUR",
    "variables": {
        "myCustomOrderId": 123
    }
}

HEADERS

{
    'Accept-Version': 'v10',
    Authorization: `Basic ${Buffer.from(`:${authToken}`).toString('base64')}`,
}

Which returns

{
    "id": 145359050,
    ...
}

Which I then generate a redirectUrl request which looks like,

PUT https://api.quickpay.net/payments/145359050/link

BODY

{
    "amount": 400,
    "continue_url": "myurl",
    "cancel_url": "myurl"
}

HEADERS

{
    'Accept-Version': 'v10',
    Authorization: `Basic ${Buffer.from(`:${authToken}`).toString('base64')}`,
}

Which returns

{
    "url": "https://payment.quickpay.net/payments/..."
}

I then redirect to the returned address.

Once on the payment page I try to complete the transaction with the Credit card test numbers but get the error message on submission.

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I know the test cards work as per the example here and I've added a payment method for VISA like so,

enter image description here

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I'm assuming I've miss-configured my store? Has anyone run into an issue like this?