ERR_NGROK_SHIP_BUILD_CONFIG_PROVIDER_UNSUPPORTED: Build provider PROVIDER is not supported - ngrok documentation

What does ERR_NGROK_SHIP_BUILD_CONFIG_PROVIDER_UNSUPPORTED mean?

ngrok returns ERR_NGROK_SHIP_BUILD_CONFIG_PROVIDER_UNSUPPORTED with this message:

Build provider <PROVIDER> is not supported. Allowed: 'dockerfile' and 'automatic'.

Where can I get more help with ERR_NGROK_SHIP_BUILD_CONFIG_PROVIDER_UNSUPPORTED?

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