When hitting the api I get a Unsupported Payment error on confirm stage; Get request on order shows payment info w/ last four

[quesurifn]

When I use authorize.net live, with the api it
{ error: 'The order could not be transitioned. Please fix the errors and try again.',
errors: { base: [ 'That payment method is unsupported. Please choose another one.' ] } }
on confirm stage.

We are using authorize.net..

When I do a get request on the order number, cc_type is missing but last 4, exp and name are all listed as a payment source.

Context

I am trying to follow this guide: http://guides.spreecommerce.org/api/checkouts.html
with the exception of step one passing in JSON to add items to cart and step two hits the endpoint /api/v1/orders/:number.json?order_token=###&order[email]=email@address.com

Step three starts at the delivery step.

When adding a payment method we use

{
  "order": {
    "payments_attributes": [
      {
        "payment_method_id": "1"
      }
    ]
  },
  "payment_source": {
    "1": {
      "number": "4111111111111111",
      "month": "1",
      "year": "2017",
      "verification_value": "123",
      "name": "John Smith"
    }
  }
}

If the payment gateway ID we use is 4 it looks like this:

{
  "order": {
    "payments_attributes": [
      {
        "payment_method_id": "4"
      }
    ]
  },
  "payment_source": {
    "4": {
      "number": "4111111111111111",
      "month": "1",
      "year": "2017",
      "verification_value": "123",
      "name": "John Smith"
    }
  }
}

Payment methods 1, 2 and 3 do not exist in the table

Expected Behavior

{
...
"state": "confirm",
...
"payments": [
Status:200

{
    "id": 3,
    "source_type": "Spree::CreditCard",
    "source_id": 2,
    "amount": "65.37",
    "display_amount": "$65.37",
    "payment_method_id": 1,
    "response_code": null,
    "state": "checkout",
    "avs_response": null,
    "created_at": "2014-07-06T19:55:08.308Z",
    "updated_at": "2014-07-06T19:55:08.308Z",
    "payment_method": {
      "id": 1,
      "name": "Credit Card"
    },
    "source": {
      "id": 2,
      "month": "1",
      "year": "2017",
      "cc_type": null,
      "last_digits": "1111",
      "name": "John Smith"
    }
  }
],

Actual Behavior

errors: { base: [ 'That payment method is unsupported. Please choose another one.' ] } }

Possible Fix

N/A

Steps to Reproduce

Spin up spree server on either 3.1 OR 3.2,
Curl the api as this script does:
https://pastebin.com/n759FHN6

very much like

http://guides.spreecommerce.org/api/checkouts.html

Your Environment

MACOSX Sierra
Chrome
Rails: 5.0.1
Spree: 3.2.0 && 3.1.0
GEM:Link