Unlawful occupation of locked resort? (8)
I believe the answer is:
trespass
'unlawful occupation' is the definition.
(being somewhere unlawfully)
'locked resort?' is the wordplay.
I cannot really see how this works, but
'resort?' could be 'spa' (spa is a kind of resort) and 'spa' is located in the answer.
The remaining letters 'tress' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'of' is the link.
(Other definitions for trespass that I've seen before include "Enter land illegally" , "sin in the eyes of the church" , "offence" , "Wrong" , "Intrude, encroach" .)