Exact payment for haven Gerald conserves (6)
I believe the answer is:
avenge
'exact payment for' is the definition.
(I've seen this in another clue)
'haven gerald conserves' is the wordplay.
'AVENGE' is hidden within the letters.
However, I'm not sure how this is indicated.
Can you help me to learn more?
(Other definitions for avenge that I've seen before include "Dish out a dose of own medicine" , "eg Nave (anag.)" , "Exact retribution, take satisfaction for injury" , "To seek vengeance" , "Get back at for (a wrong)" .)