Due to systemd limitation causing regression on AD managed systems, fix for CAP_WAKE_ALARM provided in Plasma 6.4.0 release was partially reverted in powerdevil. If your distribution wants to provide support for alarm wakeups from suspend on Plasma Mobile device, Please manually override plasma-powerdevil.service systemd user unit to pass CAP_WAKE_ALARM in AmbientCapabilities.
Same , sometimes it works and other times it requires extra steps to unlock through a vtty.