Cover for mattress inappropriate leading to reprimand (7-3)

I believe the answer is:

ticking-off

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'cover for mattress inappropriate leading to reprimand' is the definition.
I can't judge whether this definition defines the answer.

'cover for mattress inappropriate leading' is the wordplay.
I cannot really see how this works, but
'mattress' could be 'tick' (tick is a kind of mattress) and 'tick' is present in the answer.
'leading' could be 'in' (in government) and 'in' is located in the answer.
The remaining letters 'goff' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?

I've seen this clue in The Independent.

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