first thing first, install the cabin air filter, its tray is behind the glove box.
its available from honda for 2000 rupees. when you use AC or heater direct dust will come in until you install the cabin air filter.
honda should provide that with every car but sadly they are cheap people.
ask honda of cabin airfilter and they guy will install it for you aswell.
there is a tray behind glove box which becomes visible when you open glove box. the air filter slides in that.
you are welcome