---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/52311#article
headline: "52311: Delivery callback invocation failed"
url: https://www.twilio.com/docs/api/errors/52311
inLanguage: en
dateModified: 2026-03-11T20:43:38.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 52311: Delivery callback invocation failed

Log Type: TWILIO

Log Level: ERROR

## Description

Notify is unable to invoke the given callback

### Possible causes

Invalid callback URL or Internal Server Error

### Possible solutions

Check the callback URL