Again lack confidence in fieldwork (7)
I believe the answer is:
redoubt
I believe this is a double definition.
'again lack confidence in' is the first definition.
('doubt' can be a synonym for 'lack confidence in' so perhaps 'redoubt' is OK for 'again lack confidence in')
'fieldwork' is the second definition.
(I've seen this before)
(Other definitions for redoubt that I've seen before include "Tube rod (anag) - fortification" , "Defensive outwork" , "fortress" , "Temporary or outward fortification" , "Keep losing confidence in" .)