---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/64109#article
headline: "64109: ConversationRelay: Concurrency limit reached"
url: https://www.twilio.com/docs/api/errors/64109
inLanguage: en
dateModified: 2026-09-30T17:26:57.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 64109: ConversationRelay: Concurrency limit reached

Log Type: APPLICATION

Log Level: ERROR

## Description

The call was rejected because the maximum number of concurrent sessions was temporarily reached.

### Possible causes

A sudden surge in call volume temporarily exceeded available system capacity.

### Possible solutions

* Retry the connection after a brief delay if your application supports automated retries.
* If you experience frequent or sustained 64109 errors during normal traffic, please contact Twilio Support.