Indian Railways — about issue of a wrong ticket

Address:

Kolkata, West Bengal

Dear sir,
I had booked a ticket for sealdah rajdhani to new delhi for 14-09-17. But i was issued a ticket for hwh-nyd.
Kindly check my requisition slip as well. That reads a ticket for sealdah as the boarding station.
Assuming i have a ticket for my desired boarding station i boarded the train on 14-09-17. Which later to my despair (When asked by the ttte) realised it to be a wrong ticket. My ticket details are given below... Kindly guide me what and how do i get the refund of the same as i had to issue a new ticket from asansol.
Pnr:[protected].
Seeking for a positive response from your esteemed end.
Thanking you.
Regards,
Hakikat rai kapoor.