A less corrupt mistake in receipt (5,4)

I believe the answer is:

sales slip

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'receipt' is the definition.
I don't know anything about this answer so I cannot judge whether this works.

'a less corrupt mistake' is the wordplay.
'corrupt' is an anagram indicator (a corrupted form).
'mistake' becomes 'slip' (a slip is a blunder or mistake).
'a'+'less'='aless'
'aless' is an anagram of 'sales'.
'sales'+'slip'='SALES SLIP'

'in' acts as a link.

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I've seen this clue in The Daily Express.

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