Having 2 keyboard layout in my kubuntu 20.04
I set Right Alt hot keys in Main Shorts : https://prnt.sc/6BELdro2eHZc Opening Advanced tab I see “Switching to another layout” block with “Right Alt” option set : https://prnt.sc/o8uRyOHM7-VE But if in default english layout I press “Right Alt” key I have ukrainian language set as current. But pressing “Right Alt” key one more time my layout did not swithced to englisg as I expeceted. Did I miss some options in my layouts options ?
You missed the fact that when the Ukrainian layout is active, Right Alt is dedicated by default to serve as the key to access 3:rd and 4:th level symbols. So since Right Alt conflicts with that other function, it's not a good choice as the shortcut to switch layout.
My primary advice would be to simply choose some other shortcut for layout switching.