ERR_NGROK_9024: The account ACCOUNT is not authorized to use the requested leg number LEG - ngrok documentation

What does ERR_NGROK_9024 mean?

ngrok returns ERR_NGROK_9024 with this message:

The account <ACCOUNT> is not authorized to use the requested leg number <LEG>.

Where can I get more help with ERR_NGROK_9024?

Email support@ngrok.com and include the error code.