Hi,

I’m trying to create a new invoice on Xero using the API, but i’m running into an issue when trying to send multiple line items to Xero. 

My line item formatter:
 

My create invoice step, with error:
 

Here’s my code:

const perform = async (z, bundle) => {
  const options = {
    url:
      'https://api.xero.com/api.xro/2.0/Invoices/',
    method: 'POST',
    headers: {
      Accept: 'application/json',
      Authorization: `Bearer ${bundle.authData.access_token}`,
      'Xero-tenant-id': bundle.inputData.TenantID,
    },
    params: {
    },
    body: {
      Type: 'ACCREC',
      Status: 'AUTHORISED',
      DueDate: bundle.inputData.DueDate,
      InvoiceNumber: bundle.inputData.InvoiceNumber,
      Contact: {
        ContactID: bundle.inputData.ContactID
      },
      LineItems:  
        bundle.inputData.LineItems
      ],
    },
  };

  return z.request(options).then((response) => {
    response.throwForStatus();
    const results = response.json;

    // You can do any parsing you need for results here before returning them

    return results;
  });
};

module.exports = {
  operation: {
    perform: perform,
    inputFields: n
      {
        key: 'TenantID',
        label: 'Organisation',
        type: 'string',
        default: '389eced2-4a0a-4b2a-adb5-02c67183e5ef',
        required: true,
      },
      {
        key: 'ContactID',
        label: 'Contact ID',
        type: 'string',
        required: true,
      },
      {
        key: 'InvoiceNumber',
        label: 'Invoice Number',
        type: 'string',
        required: true,
      },
      {
        key: 'DueDate',
        label: 'Due Date',
        type: 'string',
        required: true,
      },
      {
        key: 'LineItems',
        label: 'Line Items',
        type: 'string',
        required: true,
      },
    ],
  },
  key: 'create_new_proforma_invoice',
  noun: 'Pro forma',
  display: {
    label: 'Create pro forma invoice',
    description: 'Creates a new pro forma invoice on Xero',
    hidden: false,
    important: true,
  },
};

It’s throwing the following error:

The app returned "JSON for post data was invalid,Error converting value "{ "Description": "my test text here...".

It doesn’t seem to like the line item data that I passed in.  Any ideas how to fix?