Declined to have keys made (11)

I believe the answer is:

degenerated

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'declined' is the definition.
(degenerating is a kind of declining)

'have keys made' is the wordplay.
'have keys' becomes 'de' (I can't justify this - if you can you should believe this answer much more).
'made' becomes 'generated' (generating is a kind of making).
'de'+'generated'='DEGENERATED'

'to' acts as a link.

Can you help me to learn more?

(Other definitions for degenerated that I've seen before include "got worse" , "Worsened" .)

I've seen this clue in The Mirror and The Daily Express.

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