Change summoner spells position

Why can't we change the summoner spell's position right and left (just the position, not the spell itself) without having to change the key binding? Sometimes when I'm playing with unsealed spellbook I change my (F) for another spell and when I change it back, usually to the other key (D), I'm stuck with to the wrong key, and either I have to use D or I have to change the keybinding for the spells. But when I look at my spells my brain gets tricked to think I have a summoner up, but it's the other one.