---
page_type: error
code: 63021
message: "63021: Channel invalid content error"
level: ERROR
product: Programmable SMS
---

## Description

Message contains content that is rejected or unsupported by the messaging channel.

### Possible Causes

- Unable to upload the media used in the message because it is not supported by the messaging channel.
- Message contains components not supported in selected messaging channel
- Length of the the template text exceeds the allowed length of 1024 for WhatsApp.
- Length of button text exceeds maximum length of 25 characters for approved WhatsApp templates or RCS suggestions and 20 characters for in session WhatsApp templates.

### Possible Solutions

- Inspect the media files being sent and confirm their MIME type is in fact supported by the messaging channel.
- Confirm message components follow character limitations, proper formatting, and channel specific rules mentioned in docs if applicable.
- Confirm WhatsApp template sends do not exceed 1024 characters, which can occur when placeholder text substitutions or translations are too long.