> ## 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 501

## ERR\_NGROK\_501

Only paid accounts can reserve addresses.
Your account can't reserve addresses.

Upgrade to a paid plan at [https://dashboard.ngrok.com/billing/choose-a-plan](https://dashboard.ngrok.com/billing/choose-a-plan)

## 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_501)