---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/19004#article
headline: "19004: Invalid or missing Contact input"
url: https://www.twilio.com/docs/api/errors/19004
inLanguage: en
dateModified: 2026-06-08T11:29:20.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 19004: Invalid or missing Contact input

Log Type: APPLICATION

Log Level: ERROR

## Description

This error occurs when you send a contact request body with invalid or missing input. If you use Bulk Upsert Contacts, Twilio returns validation details for each `correlation_id` through `error_code` and `error_messages` so you can identify the contact record that failed.

### Possible causes

* A required field is missing from the contact payload.
* The payload includes a duplicate field or an invalid field name.
* The request body is malformed or includes unsupported fields for the contact endpoint you called.
* If you are creating a contact, the payload may be missing a supported identifying field such as `first_name`, `middle_name`, `last_name`, `legal_name`, `preferred_name`, `unique_customer_provided_id`, or `channel`.

### Possible solutions

* Validate the request body against the Contact API schema before you retry the request. If you use Bulk Upsert Contacts, include the required `items` array.
* Add any missing required field, remove duplicate or unsupported fields, and correct invalid field names before resubmitting the request.
* If you use Bulk Upsert Contacts, review the `error_code` and `error_messages` values returned for each `correlation_id` to identify the exact contact record that failed validation.
* If you send a phone number in `contact_id`, format it in `E.164`.
* If you are creating a contact record, include at least one supported identifying field such as `first_name`, `middle_name`, `last_name`, `legal_name`, `preferred_name`, `unique_customer_provided_id`, or `channel`.

#### Additional resources

* [Contact API](/docs/messaging/features/contact-api)
* [Compliance Toolkit for Programmable Messaging](/docs/messaging/features/compliance-toolkit)
* [Consent Management API](/docs/messaging/features/consent-api)