Why didn't spring begin?

Lunar calendar and Gregorian calendar are calculated in different ways.

The lunar calendar is a combination of yin and yang, taking into account both the moon's profit and loss cycle and the earth's cycle around the sun, that is, one year. The Gregorian calendar that we commonly use now is divided according to the time that the earth goes around the sun once, which is about 365.2422 days. In order to solve the gap between the lunar calendar and the solar calendar, the lunar calendar adopts the method of "fixed leap month", that is, there will be a leap month every four years to ensure the synchronization of the lunar calendar and the solar calendar. However, even so, there will still be a slight gap between the lunar calendar and the solar calendar, which may lead to the absence of beginning of spring in the lunar calendar in some years. For example, 2024 is a leap year, and there is one more February, so there are 366 days in the lunar year. Beginning of spring usually occurs on February 3rd or 4th every year, so there will be no solar term of beginning of spring in the lunar calendar in 2024.