How to prevent root account pass from being changed ?

[kobbycyber]

Hello please does anyone know how to prevent a user in a group assigned system user access privilege to only that group it is in ?
I did that to a group and a user in that group can change password of administrator and disable account any fix around this would be appreciated.
I tried to add a <readonly/> in xml /conf/config.xml but seems to be overwritten and does not protect root account thanks.