---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/13249#article
headline: "13249: Dial: Invalid username or password attribute"
url: https://www.twilio.com/docs/api/errors/13249
inLanguage: en
dateModified: 2026-06-09T11:00:42.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 13249: Dial: Invalid username or password attribute

Log Level: WARNING

## Description

Twilio returns this warning when the `username` or `password` attribute on the `<Dial>` noun is invalid. This usually happens when you use `<Sip>` with missing, malformed, or unsupported authentication credentials.

### Possible causes

* The `<Sip>` noun inside `<Dial>` includes an empty `username` or `password` attribute
* The `username` or `password` attribute contains an invalid value
* You provided authentication attributes in a format that Twilio cannot use for SIP authentication
* The generated TwiML includes a typo in the `username` or `password` attribute name or value

### Possible solutions

* Review the `<Dial>` and `<Sip>` TwiML you return and confirm the `username` and `password` attributes are present only when needed
* Make sure both credentials are valid for the SIP endpoint you are dialing
* Verify the credentials do not contain unintended empty strings, template errors, or malformed characters
* Validate your TwiML against the `<Dial>` noun and `<Sip>` noun documentation and correct any invalid attributes before returning the response
* If you generate TwiML dynamically, log the final XML and inspect the values passed to `username` and `password`

#### Additional resources

* [TwiML Voice `<Dial>` noun](/docs/voice/twiml/dial)
* [TwiML Voice `<Sip>` noun](/docs/voice/twiml/sip)
* [TwiML for Voice](/docs/voice/twiml)