Check up in relation to order again (6)

I believe the answer is:

retell

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'to order again' is the definition.
('tell' can be a synonym for 'order' so perhaps 'retell' is OK for 'order again')

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for retell that I've seen before include "Repeat" , "Once again inform" , "Once more recount story" , "Narrate again" .)

I've seen this clue in The Times and The Sunday Times.

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