心当たりがない
Meanings
1
have no idea; have no clue; can't think of anything
Used when you cannot recall or think of any relevant information, person, or possibility. Often appears in negative form 心当たりがない. The related phrase 心当たりのない is an adnominal form.
See also: 心当たりのない
Antonyms: 心当たりがある
I have absolutely no idea who did such a thing.
I have no clue why she is angry.