Sounds like the author could have invested a bit more effort in world building.
The fantasy genre can be a trap for those who don't create or adopt some sort of structured metaphysical model through which magic works (and, more especially, by which it's effects on the narrative are constrained).
Ultimately the sort of "magic" in the TV series Bewitched or I Dream of Jeannie is intractable for any serious storytelling (or even comedy — beyond sight gags and slapstick).
We can't leave the audience wondering "Why didn't she just wriggle her nose or do the emphatic blinky thing to fix that?
