"Elle est partie et n'y est plus jamais retourné."

Translation: She left and never returned there again.

[LSadun]

Why is it retourne rather than retournee when we're talking about elle?

[Jojo553168]

It is a mistake.

[Seattle_Scott]

That is a very good question. It looks like an error.

[RichardSus4]

should be returnée--Duo missed it!