Order without charge, unopened after month (6)
I believe the answer is:
decree
'order' is the definition.
(I know that order can be written as decree)
'without charge unopened after month' is the wordplay.
I cannot really understand how this works, but
'month' could be 'dec' (abbreviation for December) and 'dec' is found in the answer.
The remaining letters 'ree' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for decree that I've seen before include "Direct" , "Issue an edict" , "An official order or judgement" , "Legally binding command or decision" , "Recede (anag.)" .)