Disturbed that it's not yet paid (9)
I believe the answer is:
'disturbed' is the definition.
(I know that disturbed can be written as unsettled)
'it's not yet paid' is the wordplay.
'it's not' becomes 'un' (prefix meaning 'not').
'yet paid' becomes 'settled' (I can't justify this - if you can you should believe this answer much more).
'that' acts as a link.
Can you help me to learn more?
(Other definitions for unsettled that I've seen before include "Missing work by composer, perhaps" , "Still to confirm" , "Devoid of colonists" , "Troubled" , "Nomadic lifestyle" .)