The Logitech K850 is a bluetooth keyboard that works with Apple macOS and Windows PCs.
When using it with an Apple PC you might find the that Command and Option keys have swapped or flipped functionality. Example: the Option key acts like the Command key for keyboard shortcuts and vise versa.
To reset there are 2 things you can do:
Hold the fn + o (letter O key - not zero) for 3 seconds
Turn the keyboard off and then on.
Or
Use both methods, start with option 1 then option 2.