I've noticed this when my human rogue became an arcane trickster. I didn't have access to Mage Hand until then, and even then it was only available if I picked it as one of the two available cantrip slots, even though the player handbook states an arcane trickster should have access to three cantrips, and that one must be Mage Hand. I don't know if this is a glitch or just an oversight.
