API returns wrong data

Hi, I’m using FlightXML 2.0, methods:

for tracking flight data.
When I compare data to https://ru.flightaware.com/live/flight/XXXX web page, departure, arrival, and flight times are most often different (from minutes to hours sometimes).
Sometimes I get nothing (all fields filled with 0) for future flights. For example right now I get nothing for ident N63FF

How do I get the same data as on the web-page https://ru.flightaware.com/live/flight/XXX ?

Could you provide some examples of the data being wrong from the website to the api. Also please indicate at what phase of flight these discrepancies are happening (before flight, during flight, after flight)

as an example https://ru.flightaware.com/live/flight/N633PJ

For this flight right now I get this data: