Prosperity after most of bank issue (7)
I believe the answer is:
release
'issue' is the definition.
('release' can be a synonym of 'issue')
'prosperity after most of bank' is the wordplay.
'prosperity' becomes 'ease'.
'after' is a charade indicator (letters next to each other).
'most of' means to remove the last letter.
'bank' becomes 'rely' (I've seen this before).
'rely' with its last letter taken off is 'rel'.
'ease' put after 'rel' is 'RELEASE'.
(Other definitions for release that I've seen before include "loose" , "Free - delivery" , "Issue" , "Authorise publication" , "Prisoner eagerly awaits this" .)