Once again using program in banking (10)

I believe the answer is:

reapplying

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'once again using' is the definition.
('applying' can be a synonym for 'using' so perhaps 'reapplying' is OK for 'once again using')

'program in banking' is the wordplay.
'program' becomes 'app' (type of computer program).
'in' indicates putting letters inside.
'banking' becomes 'relying' (I can't justify this - if you can you should believe this answer much more).
'app' going inside 'relying' is 'REAPPLYING'.

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I've seen this clue in The Times.

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