ERR_NGROK_15000: You are not allowed to create endpoints with subdomains on BASE

What does ERR_NGROK_15000 mean?

ngrok returns ERR_NGROK_15000 with this message:

You are not allowed to create endpoints with subdomains on <BASE>. Your account is on the <PLAN> plan, which doesn't allow starting endpoints on <BASE>.

Troubleshoot ERR_NGROK_15000 with your AI agent. Connect it to the ngrok MCP server, then ask what caused the error and how to fix it.

Where can I get more help with ERR_NGROK_15000?

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