Fulfilled order returns error instead of fulfillment API

[ecartapi]

Hello everyone

I have been encountering this error every now and then and i was finally able to replicate it. 

I have an order with 5 different items when i fulfill it i get a 422 with this message "base": [ "An error occurred, please try again" ]"

When i try to fulfill it again i get another 422 but the message is "Line items are already fulfilled"

And if i get the fulfillments of the order the first fulfillment appears on the list.

Here is the first error response.

status: 422,
    statusText: 'Unprocessable Entity',
    headers: {
      date: 'Wed, 09 Dec 2020 18:42:26 GMT',
      'content-type': 'application/json; charset=utf-8',
      'transfer-encoding': 'chunked',
      connection: 'close',
      'x-sorting-hat-podid': '73',
      'x-sorting-hat-shopid': '25183223882',
      'referrer-policy': 'origin-when-cross-origin',
      'x-frame-options': 'DENY',
      'x-shopid': '25183223882',
      'x-shardid': '73',
      'x-stats-userid': '',
      'x-stats-apiclientid': '2629615',
      'x-stats-apipermissionid': '210731040842',
      http_x_shopify_shop_api_call_limit: '8/40',
      'x-shopify-shop-api-call-limit': '8/40',
      'x-shopify-api-version': '2020-01',
      'x-shopify-api-version-warning': 'https://shopify.dev/concepts/about-apis/versioning',
      'strict-transport-security': 'max-age=7889238',
      'x-request-id': '71f2eda7-7f37-4ae3-b2ec-b5bd025a944a',
      'x-shopify-stage': 'production',
      'content-security-policy': "default-src 'self' data: blob: 'unsafe-inline' 'unsafe-eval' https://* shopify-pos://*; block-all-mixed-content; child-src 'self' https://* shopify-pos://*; connect-src 'self' wss://* https://*; frame-ancestors 'none'; img-src 'self' data: blob: https:; script-src https://cdn.shopify.com https://cdn.shopifycdn.net https://checkout.us.shopifycs.com https://js-agent.newrelic.com https://bam.nr-data.net https://api.stripe.com https://mpsnare.iesnare.com https://appcenter.intuit.com https://www.paypal.com https://js.braintreegateway.com https://c.paypal.com https://maps.googleapis.com https://www.google-analytics.com https://v.shopify.com https://widget.intercom.io https://js.intercomcdn.com 'self' 'unsafe-inline' 'unsafe-eval'; upgrade-insecure-requests; report-uri /csp-report?source%5Baction%5D=create&source%5Bapp%5D=Shopify&source%5Bcontroller%5D=admin%2Forders%2Ffulfillments&source%5Bsection%5D=admin_api&source%5Buuid%5D=71f2eda7-7f37-4ae3-b2ec-b5bd025a944a",
      'x-content-type-options': 'nosniff',
      'x-download-options': 'noopen',
      'x-permitted-cross-domain-policies': 'none',
      'x-xss-protection': '1; mode=block; report=/xss-report?source%5Baction%5D=create&source%5Bapp%5D=Shopify&source%5Bcontroller%5D=admin%2Forders%2Ffulfillments&source%5Bsection%5D=admin_api&source%5Buuid%5D=71f2eda7-7f37-4ae3-b2ec-b5bd025a944a',
      'x-dc': 'gcp-us-central1,gcp-us-central1',
      'cf-cache-status': 'DYNAMIC',
      'cf-request-id': '06ea68e3550000d0ac75380000000001',
      'expect-ct': 'max-age=604800, report-uri="https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct"',
      server: 'cloudflare',
      'cf-ray': '5ff0ddb22e02d0ac-QRO'
    },
    config: {
      url: 'https://ecart-test.myshopify.com/admin/api/2020-01/orders/2962273665098/fulfillments.json',
      method: 'post',
      data: '{"fulfillment":{"tracking_number":"987654321","tracking_company":"ENVIA","tracking_url":"https://shipping.xyz/track.php?num=123456789","location_id":32095207498}}',
      headers: [Object],
      transformRequest: [Array],
      transformResponse: [Array],
      timeout: 25000,
      adapter: [Function: httpAdapter],
      xsrfCookieName: 'XSRF-TOKEN',
      xsrfHeaderName: 'X-XSRF-TOKEN',
      maxContentLength: -1,
      validateStatus: [Function: validateStatus]
    }