/FlightXML2/InFlightInfo return empty result

hi!
i make a request:
http://flightxml.flightaware.com/json/FlightXML2/InFlightInfo?ident=N723GH

get a response:
{“InFlightInfoResult”:{“faFlightID”:“”,“ident”:“N723GH”,“prefix”:“”,“type”:“”,“suffix”:“”,“origin”:“”,“destination”:“”,“timeout”:“”,“timestamp”:0,“departureTime”:0,“firstPositionTime”:0,“arrivalTime”:0,“longitude”:0,“latitude”:0,“lowLongitude”:0,“lowLatitude”:0,“highLongitude”:0,“highLatitude”:0,“groundspeed”:0,“altitude”:0,“heading”:0,“altitudeStatus”:“”,“updateType”:“”,“altitudeChange”:“”,“waypoints”:“”}}

so, info is empty.
but at the same time, at the website you can view info,
https://flightaware.com/live/flight/N723GH

and this is not single tail number. for some numbers API works, for some not.
What could be the reason?
thanks.

InFlightInfo only returns information for flights or aircraft that have operated in the last 24 hours. The last flight operated by N723GH was on June 6.

If you need the data on recently past flights then using FlightInfoEx may be more helpful. It can return flight results for up to two weeks of historical flights.

thanks! will try it.