Why am I sometimes Libra and sometimes Scorpio?

There is no such thing. Is yours a lunar calendar or a solar calendar? This constellation is in the solar calendar. Look at the year you were born, you are a Libra, and you will never say that you have changed another constellation. You say you are a Libra, why are you mixed up with Scorpio? That's because you were born in Scorpio at the end of Libra. It can be said that you occasionally mix two constellations, but you are still a Libra. Libra is your sun sign, accounting for about 50%. It also depends on the relationship between your moon sign, rising sign and other planetary phases. Maybe you have a large proportion of Scorpio, which will show Scorpio's personality characteristics. But your sign is Libra, which is the sun sign. What constellation do we usually say you are? It's all about the sun constellation. So you are a Libra.