Indian state's area service rolled back (5)
I believe the answer is:
assam
'indian state's' is the definition.
(I've seen this before)
'area service rolled back' is the wordplay.
'area' becomes 'a' (maths abbreviation).
'service' becomes 'mass' (I've seen this in other clues).
'rolled back' is a reversal indicator.
'mass' written backwards gives 'ssam'.
'a'+'ssam'='ASSAM'
(Other definitions for assam that I've seen before include "Indian state, famed for its tea" , "Kind of Indian tea" , "Indian province" , "NE Indian state (tea)" , "Indian tea region" .)