Open the Settings app on your VIVO X9s.
Select Erase All Data (Factory Reset). You might also see an option like "Reset to Factory Settings." How to Hard Reset VIVO X9s
Scroll down and tap on More Settings (sometimes labeled "System Management" depending on your Funtouch OS version). Open the Settings app on your VIVO X9s
You will see a warning list of all data that will be removed. Confirm by tapping Reset Phone or Clear All Data . or PIN to verify your identity.
The phone may ask for your security password, pattern, or PIN to verify your identity.