You may have encountered this error message on your Minecraft server causing it to crash or prevent it from starting up. This typically means that one of your .json configuration files may have become corrupt.
The error: java.lang.NullPointerException: Exception in server tick loop
Head to the Fractal dashboard and let’s get this fixed:
  1. Stop the server
  2. Head to the file manager
  3. Find and delete whitelist.json, banned-player.json, and banned-ips.json
  4. Start the server
This will regenerate the files in a correct format for you.