Lacking key to Italy? Not a problem (9)

I believe the answer is:

atonality

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'lacking key' is the definition.
The definition and answer can be both related to communication as well as being singular nouns.
Perhaps they are linked in a way I don't understand?

'italy? not a problem' is the wordplay.
'problem' indicates anagramming the letters.
'italy'+'not'+'a'='italynota'
'italynota' is an anagram of 'ATONALITY'.

'to' acts as a link.

Can you help me to learn more?

(Another definition for atonality that I've seen is " Absence of key or mode".)

I've seen this clue in The Mirror.

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