# 21754: Opt-In Message Length Invalid

Log Type: TWILIO

Log Level: ERROR

## Description

The campaign submission could not be processed because the provided `opt_in_sample_message` was invalid. Please verify its length is between 20 and 320 characters.

### Possible causes

The opt-in message is shorter than 20 or longer than 320 characters.

### Possible solutions

Revise the opt-in message to meet length requirements.