Unable to switch languages using Fn key on MacBook Air

Tinano71 wrote:

I can't always switch between languages by pressing fn button on keyboard om my macbook air

Try using control space instead of of Fn/Globe. Caps lock is also an option between Latin and non-Latin scripts.

How to fix multilingual keyboard layout s… - Apple Community

Try going to System Preferences > Keyboard > Input Sources and make sure the shortcut for switching between languages is enabled. You can adjust the settings there to troubleshoot the issue further.

Is your MacBook updated to the latest software version?

Tinano71 wrote:

Alex, Thank you for a reply. Yes, everything's set correctly. There must be another reason.

Does Control Space work better?