Dislodging Pradeep's Phone

Turn the heater on at the highest fan speed (in a mode that sends the greatest air flow thru the duct in question). Then, insert a small length of tubing that’s attached to a vacuum source (the strongest shop vac you can find). When the sucking end of the tubing contacts the phone, hopefully the combination of push and pull (air flow and suction) will enable you to pull the phone out.