en_tn/jer/51/57.md

her princes and her wise men ... her governors, her officials, and her soldiers

The people of Babylon are spoken of as if they were the city itself, and the city is spoken of as if it were a woman. Alternate translation: "their princes and their wise men ... their governors, their officials, and their soldiers" (See: rc://en/ta/man/jit/figs-metonymy and rc://en/ta/man/jit/figs-metaphor)

they will sleep in an unending sleep and never wake up

They will be dead. See how you translated this in Jeremiah 51:39. (See: rc://en/ta/man/jit/figs-euphemism)