In the menu bar, choose Apple menu > Restart. As your Mac restarts, hold down the Command and R keys until the macOS Utilities window appears and follow the instructions.
You can configure it to only allow access to the specific SSIDs by specific groups (one group of each SSID would be easiest). Then add those groups to AD, and add the users into each group that you want to have the capability to connect.
Have you reset the settings? This will return all iDevice settings to factory defaults... you will not lose any data.... But you will have to re-enter all of the device settings.