If you lose something in the airport terminal you need to go to the Security Office and file a report.
To find the Security Office simply ask an airport security officer who are very abundant in the airport or go to the Airport Information Booth.
If you have lost something on your flight, find your airline representative immediately [before you leave the departure terminal]. Give them the flight number, your seat number and item description. Chances are the item can be recovered before the airplane leaves.
If you leave the airport your only option is to contact the airline you flew with and file a claim. With most airlines you can do this on-line.
LOST LUGGAGE & ITEMS
If any part of your luggage does not arrive in Baggage Claim then find your Airline Representative immediately. You usually have to look around for them and ask security where to find them.
Once you have found your Airline Rep you give them your flight number and a description of the missing item and the name of the hotel you are staying at.
Make sure you get a telephone number for that person or their office. Proceed to your hotel. Your luggage should be delivered to you. You can telephone the rep and inquire.
3-1-1 for carry-ons = 3 ounce bottle or less (by volume) ; 1 quart-sized, clear, plastic, zip-top bag; 1 bag per passenger placed in screening bin.
One-quart bag per person limits the total liquid volume each traveler can bring. 3 oz. container size is a security measure.
Declare larger liquids. Medications, baby formula and food, and breast milk are allowed in reasonable quantities exceeding three ounces and are not required to be in the zip-top bag. Declare these items for inspection at the checkpoint.