Rabbi Alon Anava – On the 23rd of the month of Sivan (כג׳ סיון) the decree of Haman (At the time of Mordechai and Esther) to annihilate the Jewish nation was nullified. The holy books teach us that this day (today) is a very powerful day for prayers to nullify decrees and anything bad, evil and horrible against us.
Follow this link https://www.atzmut.org/sivan23 to find the prayers and text to read.