So you followed this to get back to a working system? PiAware - build your own ADS-B ground station for integration with FlightAware - FlightAware
Red light just means the device has power.
If you have another sd-card, you can try that.
With a fresh format you’ll need to claim the new station.
Or you’ll have to enter your old feeder-id: For Beginners - How to Get Back Existing Station Number in A Fresh Install