Different responses if mail gives wrong idea (5,10)

I believe the answer is:

false impression

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'wrong idea' is the definition.
The definition suggests a singular noun which matches the answer.

'different responses if mail' is the wordplay.
'different' is an anagram indicator (letters placed in a different order).
'responses'+'if'+'mail'='responsesifmail'
'responsesifmail' is an anagram of 'FALSE IMPRESSION'.

'gives' is the link.

Can you help me to learn more?

I've seen this clue in The Daily Express.

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