Not set out but being tried out (2,4)

I believe the answer is:

on test

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'but being tried out' is the definition.
I can't tell whether this definition defines the answer.

'not set out' is the wordplay.
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
'not'+'set'='notset'
'notset' is an anagram of 'ON TEST'.

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