Tamil Nadu Express - தங்களை அன்புடன் வரவேற்கிறது - Swaroop Kutti

As per rules :
REFUND DUE TO LATE RUNNING OF TRAINS
No cancellation charge or clerkage shall be levied and full fare shall be refundable to all passengers holding Reserved, RAC, and Waitlisted tickets, if the journey is not undertaken due to late running of the train by more than 3 hours of the scheduled departure of the train from the journey commencing station provided that the ticket is surrendered upto the maximum time limits prescribed in clause (c) of sub-rule (1) of rule 6 .Which is given below:
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refund will be permitted even after the departure of train in the event of train running more than 3 hours late and that the time limits will be up to 3 hours if the distance of the ticket is up to 200Kms., up to 6 hours if the distance of the ticket is 201-500 Kms. and up to 12 hours after the departure of the train if the distance of the ticket is more than 500 Kms.
This is for tickets booked at PRS counters. AS yours is a e-ticket, you will have to login into your account in IRCTC and file TDR. There you have select"Train late for more than 3 hours". Full fare will be refunded after TDR is processed.