Awaiting refund for prebooked seats not given

We booked online 5 tickets WITH pre booked & paid for seats on QF64 to Sydney on 29/6/15 under ref 6BMMEU. We paid for seats no 65J, 65K, 66H, 66J & 66K. We were given 65D,65E,65F, 65G & 65H . We tried speaking to the staff onboard the aircraft and were told we must just sit and be happy we have seats close by????? I was traveling with my daughter to assist with her 3 children ages 2,3 & 7. I have been trying to get a refund /reply from Qantas since early July 2015 as well as emails to so many depts that I keep getting referred to. I have filled in forms online but no one no one at Qantas gets back to me. All I want is Qantas to refund us the money for the seats we paid for that they never gave to us