ARK automatically makes local backups of your world which are simple to restore if necessary, here's how:
1. Login to the Game Control Panel at https://game.auxilex.com
2. Ensure your server is in the Stopped state
3. Click Restore Map Backup
4. Select the timestamp (Format: Map_Date_Time) you'd like to revert to in the dropdown list then click Execute
5. Go back to your game server's main control page and start the server.