First things first, before proceeding please make sure you have a .jex backup. You can make it from your desktop.
Next, according to the log, there were some errors in the initial sync. Could you reinstall the app and try syncing again? Give it time for the initial sync.
Better to set up auto-lock for as much time as your system would allow. It's because the app doesn't sync when the phone is locked or is in background, so it must be kept foreground and unlocked.