In The Cutting of My Long Hair, what cultural practice was Zitkala-Sa forced to undergo that upset her deeply?

In “The Cutting of My Long Hair,” Zitkala-Šá was forced to undergo the cultural practice of having her long, cherished hair cut off. This act deeply upset her as it was a symbol of her Native American identity and pride. In her culture, long hair represented strength and connection to her heritage. The missionaries at the boarding school, however, saw it as a symbol of barbarism and forced her to conform to their standards of “civilization.” The emotional trauma of this cultural imposition highlights the internal conflict between her native identity and the pressures of assimilation.

This question related to Chapter 6 English Vistas Class 12th NCERT.
From the Chapter 6, Memories of Childhood.
Give answer according to your understanding.