Group that's not working provide a counterbalance (6)
I believe the answer is:
offset
'a counterbalance' is the definition.
(I know that counterbalance can be written as offset)
'group that's not working' is the wordplay.
I cannot really see how this works, but
'group' could be 'set' (both can mean a collection) and 'set' is present in the answer.
'not' could be 'o' (I've seen this in other clues) and 'o' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
'provide' acts as a link.
Can you help me to learn more?
(Other definitions for offset that I've seen before include "Compensate(d) for" , "Place at an angle to the main alignment" , "Amount by which a thing is out of line" , "Counterbalance or compensate for" , "Distance out of line" .)