If you are using schedule Charging then schedule charging are not designed to stop the charging at a certain percentage, they are designed to slow down the charging rate to slow down the battery degradation. It will charge normally upto 80% and then slow down and it will reach 100% before the scheduled time. Also, its mentioned that the phone will be charged before the end time. It will recharge your phone before the end time approximately (45 mins to 1hr before) Keep a check on battery health. Thanks!
When the Start and End Times are set correctly, Battery Care can be used to ensure that the battery does not charge more than 81%. Many users have confirmed here that this is exactly how they use Battery Care. However, it would be very useful if Battery Care also had a switch that would allow to reset the battery statistics not at the standard 90%, but at 80%. Read this thread for example: https://zentalk.asus.com/en/discussion/28485/scheduled-charging-battery-care-bug