Section 3(2)(a) in The Railway Passengers (Cancellation of Ticket and Refund of Fare) Rules, 2015
(a)in case of tickets which were issued for travel from a station other than the ticket issuing station, refund of fare shall be admissible at -(i)the ticket issuing station, if the ticket is surrendered before the scheduled departure of the train from the station from where the ticket is valid for travel; and(ii)the journey commencing station, if the ticket is surrendered within the time limits prescribed in these rules; and