Why i can't install these *ZenFone Selfie (ZD551KL)

[godfred]

Please tell us some basic information before asking for help:
Model Name:ASUS_Z00UD
Firmware Version: 5.0.2
Rooted or not:
Frequency of Occurrence:
APP Name & APP Version (If your issue relates to the app): Asus Support Version 2.0.5.6_151225, cant install system update, Messenger and Facebook
In addition to information above, please also provide as much details as you can, e.g., using scenario, what troubleshooting you've already done, screenshot, etc.
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[Christine_ASUS]

Hi godfred
Thank you for your asking. Kindly provide the information below so that we can better assist you.
https://www.asus.com/ph/Phone/ZenFone_Selfie_ZD551KL/HelpDesk_BIOS/
1. Your current firmware version
Settings>System>About Phone>Build Number
2. Which firmware version do you want to upgrade?
3. Facebook and Messenger are pre-installed apps, please try the Factory Reset.
4. Have you ever unlocked, rooted, installed custom rom in your device?