Hi try the below:
Re-plug the cable and unplug, see if the notification disappear
Try blowing gently around the Type C port for any dust particle
Check under safe mode - Hold power button for 5 seconds => When the screen flashes with option => Press & hold power option => You will get an option to restart in safe mode
Factory reset would be helpful
Last would be to visit the nearest service center, I feel above steps should make the icon disappear .
Due to the lockdown, service centers may not be functional. Kindly call the service center before you visit one.
https://www.asus.com/in/support/service-center/india