Indian Railway Catering & Tourism Corporation [IRCTC] — Question on IRCTC ticket authenticity

Address:	Patna, Bihar, 800025
Website:	WWW.IRCTC.CO.IN

Dear Sir/Mam
I had booked one ticket for my sister Puja kumari on 14th nov 2016, Transaction id [protected], PNR [protected], in Train 12365 from Patna to Ranchi and the date of journey was 15th Nov 2016 from IRCTC Website login id abhayril05.
My allotted seat no. was 30/window side in D11 Coach.when i reached the mentioned seat number i found one person already occupied that seat after inquiry i found that he also had counter ticket of same allotted seat i.e 30/window side in D11 Coach.
Confirming the same from Railway staff i found that in the list which was available with railway staff the seat was allotted to that guy who had occupied the seat and requesting for resolution to provide another seat to my sister the TT denied that he don't have any spare seat and further he said that he is not responsible for such situation go and complain in DRM Office, see how rude a person can be is this the humanity and he is working for the people and using such absurd language .
I was surprised that how such a big organisation can do a blunder mistake of allotting the same seat to two person and making profit with customer money.
She had to travel alone and she had her examination on next day, can you imagine the amount of tension generated by such kind of situation.
I want to raise this complain to the top management so that the same can't be happen again with another customer and request to refund my ticket cost with compensation amount.