Why do people fail to see Jesus’ birth of date in Gospel?
Because they use modern calendar to calculate ancient events.
They use modern Gregorian calendar to calculate events in Gospel, which originated before 100 AD. In fact, Gregorian calender has prevailed since 1582 AD.
Gospel was written before 100 AD. In this era, ancient people in Palestine used Julian and Hebrew calendars, instead of Gregorian calendar.
Use Julian and Hebrew calendars in your calculation, then, you will see chronology of Christmas and Jesus’ date of birth in the Bible.