Not working? Finally seek a position (5)
I believe the answer is:
kaput
'not working?' is the definition.
(kaput can mean broken)
'finally seek a position' is the wordplay.
'finally' says to take the final letters.
'position' becomes 'put' (synonyms).
The final letter of 'seek' is 'k'.
'k'+'a'+'put'='KAPUT'
(Other definitions for kaput that I've seen before include "Broken, put out of use" , "Completely broken down" , "Broken or finished - in Germany" , "Broken and useless" , "Defunct (informal)" .)