Mitsubishi Electric India — AC not working

Dear sir,
I had purchased Split AC from himanshu enterprises, Indore (M.P)
Just after the purchase i was facing problem in A.C
it is not cooling and also making some noices.
after repeated complaint to himanshu enterprise and also to Mitsubishi technician Mr. Soni my issue is not yet been resolved
it has been more than 6 months, as we are out of patience no we want a readily replacement of A.C or else we will be forced to file a complaint