Thank you for your sharing. Please check if you have opened "Battery Care"
If you have opened "Battery Care", schedule charging will charge the phone to 80% first, then charge to 100% in last 2 hours of the setting period.
Also, you can enter "Safe Mode" to charge your phone to see if the situation remain the same.
# How to enter and exit "Safe Mode"https://www.asus.com/support/FAQ/1005163/
Does the issue start after any firmware/app download or update? Please try to re-insert the charger and re-boot the phone. If the phone turn off, could it be charge to 100%? If it could, please provide me the screenshot of
②Setting>Battery>3 dots on the top"Show app usage"
Furthermore, how old is your battery? You can also contact ASUS repair center in the country of your residence to check your battery health: https://www.asus.com/support/Service-Center-All-Countries/
If it is impossible to access the service center during Covid-19 period, please try Call us: https://www.asus.com/support/CallUs