Kill time more than once when things don't go so well
I believe the answer is:
off-days
'than once when things don't go so well' is the definition.
I can't judge whether this definition defines the answer.
'kill time more' is the wordplay.
'kill' becomes 'off' ('off' can informally mean 'murder').
'time' becomes 'days' (I can't justify this - if you can you should believe this answer much more).
'more' means one lot of letters go next to another (some letters added to the previous ones).
'off'+'days'='OFF DAYS'
Can you help me to learn more?
(Another definition for off-days that I've seen is " When one is out of sorts".)