The Portainer server restarts every 5 minutes before the admin account is created
When the Portainer server starts, waits 5 minutes for a user to create the admin account. If no account created in the first 5 minutes, the server stops with error code 1, message:
No administrator account was created after 5 min. Shutting down the Portainer instance for security reasons.
To keep the Portainer server running, with your web browser navigate to the web UI on port 9000 and enter a password for the admin account.