According to her, I'm wrong again (4)

I believe the answer is:

mimi

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'according to her' is the definition.
I can't judge whether this definition defines the answer.

'i'm wrong again' is the wordplay.
'wrong' is an anagram indicator.
'again' becomes 'mi' (I can't justify this - if you can you should believe this answer much more).
'im' is an anagram of 'mi'.
'mi'+'mi'='MIMI'

Can you help me to learn more?

(Other definitions for mimi that I've seen before include "I'm, I'm mad about the heroine in 'La Boheme'" , "Tragic Parisienne" , "Bohemian girl" , "Starving character of "La Boheme"" , "Puccini's seamstress" .)

I've seen this clue in the Evening Standard.

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