ERR_NGROK_SHIP_PUBLISH_TARGET_REPOSITORY_PREFIX_REQUIRED: The 'repository_prefix' field must not be empty for a KIND publish target - ngrok documentation

What does ERR_NGROK_SHIP_PUBLISH_TARGET_REPOSITORY_PREFIX_REQUIRED mean?

ngrok returns ERR_NGROK_SHIP_PUBLISH_TARGET_REPOSITORY_PREFIX_REQUIRED with this message:

The 'repository_prefix' field must not be empty for a <KIND> publish target.

Where can I get more help with ERR_NGROK_SHIP_PUBLISH_TARGET_REPOSITORY_PREFIX_REQUIRED?

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