Indian Railways — ticket booked for 1st ac, as per chart also got confirmed but in train seat allotted in 2nd ac.

Train no 15910 doj.20.11.17 pnr no [protected]. As ticket booked for 1st ac and as per chart confirmed in 1st ac, but in the train tt sir alloted seat in 2nd ac, as told that coach is not attached.
1st what about refund of difference.
2nd online status and station chart also showing 1st ac coach, why it is not updated.
3rd rail department will responsible for misguide as coach were attached in the last but as per chart showing 4th from engine. Due to small kid i have faced lot of problem to catch the coach. Who is responsible for that and need to take appropriate action again concern.