Please follow steps below for troubleshooting:
- Uninstall apps that are not often used:Settings > Apps > (select an app) Uninstall
- Move apps that are stored in internal space to SD card:Settings > Apps > tap MOVEABLE > select an app > Move to SD card
- Change default app installation location to SD card:Settings > ASUS customized settings > App installation settings > Prefer external storage
- Delete data that are not in use