Crossword Genius

IT handles customer calls (9)

Ross

I believe the answer is:

usernames

I'm a little stuck... Click here to teach me more about this clue!

'it handles' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'customer calls' is the wordplay.
'customer' becomes 'user' (I've seen this in another clue).
'calls' becomes 'names' ('name' can be a synonym of 'call').
'user'+'names'='USERNAMES'

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I've seen this clue in The Guardian.
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