ERR_NGROK_SHIP_CONTAINER_IMAGE_REFERENCE_INVALID: The image reference IMAGE is not valid: REASON - ngrok documentation

What does ERR_NGROK_SHIP_CONTAINER_IMAGE_REFERENCE_INVALID mean?

ngrok returns ERR_NGROK_SHIP_CONTAINER_IMAGE_REFERENCE_INVALID with this message:

The image reference <IMAGE> is not valid: <REASON>

Where can I get more help with ERR_NGROK_SHIP_CONTAINER_IMAGE_REFERENCE_INVALID?

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