Reports a mental breakdown? It's none of your business! (8,6)

I believe the answer is:

personal matter

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'none of your business' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'reports a mental breakdown?' is the wordplay.
'breakdown?' indicates anagramming the letters (I've seen 'breakdown' mean this).
'reports'+'a'+'mental'='reportsamental'
'reportsamental' is an anagram of 'PERSONAL MATTER'.

'it's' acts as a link.

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I've seen this clue in the Sydney Morning Herald.

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