What happened to mellony becoming human from a magic mask?

I love the lore in the new episode, but doesn't this fight against how mellony was made? She was made with a magic mask, she didn't grow up to become this. She was a normal Mellon before she got the mask that made her human, I think the writers should have came up with something else.

For example, mellony is scared of loosing her friend, and since near the beginning Bob praise the hot dog. Meggy throws it into mellony mouth, there for causing her to calm down