When you find that you can't launch the camera , please follow the below steps for troubleshooting：
The Front/ Rear camera function are not normally working
1. Reboot your phone/pad and launch the camera again. (Check if both front & rear camera are working)
2. Clear the camera cache : Go to Settings > Apps & notifications > App info > Camera > Storage & memory > Clear cache. (Example : Android 😎
3. Update the Camera app from Google Play：Then start the Camera ( front & rear camera) again.
4. Update the firmware to the latest version ：Settings > System > System updates > Check now.
5. Access to Safe Mode : By long pressing the power key > Tap and hold Power Off option in menu> Tap OK. If your phone works well in the Safe Mode but cannot work normally after you restart the device , such situation might result from the third-party applications. We suggest you backup all your data and perform the factory data reset.
6. Backup your data and Perform factory data reset.
Note: Once the factory data reset is completed, all data, apps, settings and personal information will be deleted after initialization.
7. If the above steps can't solve your issue, please contact ASUS Product Support for further assistance.