There are no scriptures that state the preexistance of souls.
God creates the soul with the body, 7 And the LORD God formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a living soul.
It is important because it leads to all kinds of heresies, transmigration of souls, reincarnation, innate knowledge of the soul etc.
If and when I come across the Scriptures again any time soon, I’ll post them.
I can’t remember the key words well enough to search for them.
I think you are wrong.