Lucélio Gomes de Freitas wrote:

I open systemsetting to change timezone to (GMT-3), and after clicking "apply", I get the error on KDE control module, "Not possible to execute/authenticate the accion: 6", and timezone is updated. After the restart of the system, my timezone setting is wrong again, and get to the previous(GMT).

Sounds like SELinux being a PITA, try disabling SELinux.

Kevin Kofler