---
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"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/32105#article
headline: "32105: SIP: Invalid contact header"
url: https://www.twilio.com/docs/api/errors/32105
inLanguage: en
dateModified: 2026-03-11T20:01:16.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 32105: SIP: Invalid contact header

Log Level: WARNING

## Description

Possible loop in Contact header

### Possible causes

You're sending `127.0.0.1` or `localhost` in the Contact header which will create a loop at Twilio.

### Possible solutions

Configure your SIP stack so it populates the Contact header properly.