Fail to justify a lot of insufficient aid (9)

I believe the answer is:

undeserve

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'insufficient aid' is the definition.
I know nothing about this answer so I can't tell whether this works.

'fail to justify a lot of' is the wordplay.
'fail' becomes 'und' (I can't justify this - if you can you should believe this answer much more).
'to justify' becomes 'deserve' (I've seen this before).
'a lot of' means to remove the first letter.
'deserve' with its first letter taken off is 'eserve'.
'und'+'eserve'='UNDESERVE'

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I've seen this clue in The Times.

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