Macbook not locking when lid is closed and is logged in when opened. All settings are corrected but doesn't work.

I have a Macbook air M2 13 inch and it usually locks when I close the lid and open it again. But now it automatically is logged in and doesn't ask for any passwords even after 2 hours since it is closed. I checked online for info but all the settings I have are the correct ones for this to work. My laptop is connected to a school network and shows that I cannot change the setting for 'Require password after screen begins or turned off' as it says 'This setting has been configured by profile' and it is always 'Immediately'. I turned VileVault on and off but that didn't work. This is a security issue that must be fixed as quickly as possible.