Your previous Settings.xml file may be in the "LaunchBox/Data/Backups" folder. If it's not there, then it was replaced with the default one. It's happening when it was corrupted or manually changed.
To avoid such situations, after you have configured all your settings, make a copy of the Settings.xml file and store it in a safe location. When you get the same issue, just replace the current Settings.xml file with the saved one.