Get less, having cancelled a second order (6)

I believe the answer is:

decree

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'order' is the definition.
(I know that order can be written as decree)

I don't understand the remainder of the clue.

(Other definitions for decree that I've seen before include "Direct" , "Ordain" , "Rule" , "Official order of ruling" , "Official edict" .)

I've seen this clue in The Times.

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