Please refer to the following to flash the system back to Android P.
ASUS ZenFone 5 Software downgrade to target Image
Version: 16.0615.2002.120 (Android 9 Pie) by using MicroSD card for WW SKU only
* Please follow step 6 and ensure to backup data before downgrade.
Version Android 10 downgrade to P (1.98 GB)
Steps of Update:
1. Prepare a MicroSD card.
2. Check software version of your device**
3. Only apply to same SKU update, Example: WW->WW, CN->CN, TW->TW, ID->ID.
4. Software update cannot transfer the software SKU.
5. Wrong SKU may cause update failure, please update the same SKU version only.
6. How to manual update firmware please refer to
*How to know the device model?
Path: Settings->About-> Model number
Example: ASUS PadFone2
**How to know the device software version?
Path: Settings->About-> software information->Build number
*System upgrade may cause part of data missing, please backup your important data before system upgrading.
Sorry for any inconvenience it may be caused.