I dont know what happend it worked fine earlier I restarted the game multiple times and it still wont favorite or unfavorite
but it will let me if I have a NPC menu open WTF??? Am I missing something here

Also I didn't change any controls

Yeah I feel your pain bro, I changed my keys, worst decision I have ever made, I cant favorite stuff anymore, beth needs to address this pronto, as fighting without being able to quick select say... your potions is a real problem. tho if you didn't changed your keys... then I have no clue as to why this is happening now, it might not even be related to key changes, its just that the UI is more full of bugs than a cupboard on a filthy kitchen on summer.

I had this problem when I made the "F" key do something else. Unfortunately this breaks the favorite function. Reset the controls back to default and don't rebind that key as anything else.
Defeats the point of keybindings though.

I changed my F key to R and in some menus it's still F for me and in others it's R.
I guess I've been pretty lucky so far.