> ## Documentation Index
> Fetch the complete documentation index at: https://ngrok.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Error 210

## ERR\_NGROK\_210

The content type you specified `CTYPE` is not supported by the API. Check your API client implementation and see the list of supported content types: [https://ngrok.com/docs/api#content-types](https://ngrok.com/docs/api#content-types)

## Further help

If you're having trouble resolving this error, please reach out to [support@ngrok.com](mailto:support@ngrok.com?subject=Help%20with%20ERR_NGROK_210)