this is not a big problem at all Salik on passenger side under dash board (from foot mat side) open the clips and bring that part out. There is a filter inside. you are in need to to change it If you have done this and changed it already you are in need to go for the service of your cooling coil (which is on same location after the AC filter)
Thats It! if you don't know anyone to help you in this, you can come to us. Insha ALLAH we 'll do it.
We are located in Karachi Near Haji Mehfooz Sheermaal & Sherwani Motors (Waterpump, F. B. Area) with name Newtech Autos.
Have a happy Drive !!