It’s probably damaged. Check the message log for a message during startup.
Your current log has one year of history. I would recommend replacing the SDcard. Copy all of the files from your old card except the History log (/iotawatt/histlog.log).
When you restart, it will take a long while (probably a day or so) to build a new history log from the current log. Best not to do anything with the configuration and stop any uploaders while this is going on. You can watch the progress on the status display.