Unlucky one makes up endless resolutions. (5)
I believe the answer is:
loser
'unlucky one' is the definition.
(I've seen this in another clue)
'up endless resolutions' is the wordplay.
'LOSER' is hidden back-to-front in amongst the letters.
But, I'm unsure how this is indicated.
'makes' is the link.
Can you help me to learn more?
(Other definitions for loser that I've seen before include "A failure, also-ran" , "Unsuccessful person" , "Generally inept" , "One not winning" , "one that's been left behind" .)