You most likely want to go to:
01. Settings
02. "On my dock"
03. More Options (bottom right) -> "Show system tray icons on my dock"
If that does not help, right-click the dock itself (not an icon on it) and enable "View -> Show system tray icons" (however, this is the same thing accessed differently i guess).
If that also does not help, try right-click the dock again and go to "configure system tray icons". Here you have to select the ones it should show; maybe just all are deselected? Top shows active and bottom shows inactive ones.