Setting the clock to 12 hour format
I cannot turn my clock back to a 12 hour format? It is stuck in a 24 hr format.
iMac 21.5″ 4K, macOS 12.0
In System Preferences > Language & Region > General, deselect 24-Hour Time. Also, in System Preferences > Dock & Menu Bar panel, scroll down to Menu Bar Only section and select Clock. Deselect Use a 24-hour clock if it is selected.