TNSTC — Ticket issues

Address:

Bangalore, Karnataka

Sir, I have booked two tickets for myself and my brother online from velankanni to Bangalore on 18.01.2015. but then my brother not decided to come and we didn't cancel ticket so i can travel comfortably in two seats. but on journey conductor said you cannot travel like that some other person will come to your next seat. in that case i asked him to get the money to me from that passenger. but he said he cannot return also. i want to know is there really any rules like that. please refund my ticket fare Rs.510 PNR number - T9431467 Route no - 864UD Bus ID number E-2793 Date and time of journey - 18.01.2015, 18:35 Seat No/s - 27 &28