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# Method name: updateInvoice(id: IdAndVersion, invoiceFields: InvoiceFields, fieldMask: Array<string>)

# Method package: wixBillingBackend

# Method menu location: wixBillingBackend --> Invoices --> updateInvoice

# Method Link: https://dev.wix.com/docs/velo/apis/wix-billing-backend/invoices/update-invoice.md

# Method Description:

Update an existing invoice.

The `updateInvoice()` function returns a Promise that resolves to the ID and version of the updated invoice.

> **Note:** The customer listed on the invoice must be an existing site contact or member.



# Method Code Examples:

*** Note: do not assume any prop names or enum values other than the ones in the example.

## Update an existing invoice

```javascript
import { Permissions, webMethod } from 'wix-web-module';
import { invoices } from 'wix-billing-backend';

export const updateInvoice = webMethod(Permissions.Anyone, (id) => {
  return invoices.getInvoice(id)
    .then((result) => {
      //make some changes
      result.metadata.notes = "An updated note.";

      let updateFields = {
        "title": result.title,
        "customer": result.customer,
        "currency": result.currency,
        "lineItems": result.lineItems,
        "discount": result.discount,
        "payments": result.payments,
        "metadata": result.metadata,
        "dates": result.dates
      };
      return invoices.updateInvoice(result.id, updateFields);
    });
});

/* Promise resolves to:
 * {
 *   {
 *     "id": {
 *       "id": "1ed3a515-24f9-4039-8937-2e69b6a2f33a",
 *       "version": 31
 *     }
 *   }
 * }
 */
```

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