en_tn/est/09/01.md

the twelfth month, which is the month of Adar, on the thirteenth day

See how you translated a similar phrase in Esther 3:13.

when the king's law and decree were about to be carried out

"Carry out" here is an idiom meaning to do something that was commanded or planned. This can be stated in active form. Alternate translation: "when the people were about to obey the king's law and decree" (See: rc://en/ta/man/jit/figs-idiom and rc://en/ta/man/jit/figs-activepassive)

to gain power over them

Gaining power over people is an idiom for defeating them. Alternate translation: "to defeat the Jews" (See: rc://en/ta/man/jit/figs-idiom)

it was reversed

"the situation was reversed." The situation being reversed is a metaphor meaning that the opposite of what was expected happened. Alternate translation: "the opposite happened" (See: rc://en/ta/man/jit/figs-metaphor)