How to greet Eskimo? One that’s heartless may keep stressing an error? (3,4,4,2,2)

I believe the answer is:

rub ones nose in it

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'how to greet eskimo? one that's heartless may keep stressing' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'an error?' is the wordplay.
I cannot quite see how this works, but
'an' could be 'one' and 'one' is found in the answer.
This may be the basis of clue (or it may be nonsense).

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I've seen this clue in The Times.

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