---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/40100#article
headline: "40100: TaskRouter->Reject"
url: https://www.twilio.com/docs/api/errors/40100
inLanguage: en
dateModified: 2026-03-11T20:01:16.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 40100: TaskRouter->Reject

Log Type: APPLICATION

Log Level: ERROR

## Description

Your Reject instruction does not include a valid `activity_sid` parameter.

### Possible causes

* You did not include an `activity_sid` parameter in your `reject` instruction.
* You did include an `activity_sid` but it was invalid or no longer exists.

### Possible solutions

* Confirm a valid `ActivitySid` value is is being passed by your code into the request payload JSON's `activity_sid` parameter: `{ "instruction": "reject", "activity_sid": "WA0123456789abcdef0123456789abcdef" }`