It's OK, never (3,2,3)

I believe the answer is:

not at all

I believe this is a double definition.

'it's ok' is the first definition.
(said when someone apologises say)

'never' is the second definition.
(thesaurus)

(Other definitions for not at all that I've seen before include "acceptance of apology" , "denial" , "Don't mention it!" , "My pleasure" , "Never!" .)

I've seen this clue in The Telegraph.

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