To fix things, you need a prison officer (5)
I believe the answer is:
screw
'prison officer' is the definition.
(slang term)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for screw that I've seen before include "Fixer; twist of paper" , "Wage - prison officer" , "Bring pressure to bear" , "shot in pool hall" , "Threaded pin" .)