ERR_NGROK_6008: This endpoint is unavailable as its account is suspended due to lack of payment - ngrok documentation

What does ERR_NGROK_6008 mean?

ngrok returns ERR_NGROK_6008 with this message:

This endpoint is unavailable as its account is suspended due to lack of payment.

Where can I get more help with ERR_NGROK_6008?

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