Another summons, to that Chennai address (2,6,5)

I believe the answer is:

st thomas mount

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

'another summons to that' is the wordplay.
'another' is an anagram indicator.
'summons'+'to'+'that'='summonstothat'
'summonstothat' is an anagram of 'ST THOMAS MOUNT'.

Can you help me to learn more?

I've seen this clue in The Hindu.

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