OET interlinear 2 KI 23:23

uW Translation Notes:

Note 1 topic: grammar-connect-exceptions

כִּ֗י אִם־בִּ⁠שְׁמֹנֶ֤ה עֶשְׂרֵה֙ שָׁנָ֔ה לַ⁠מֶּ֖לֶךְ יֹֽאשִׁיָּ֑הוּ נַעֲשָׂ֞ה הַ⁠פֶּ֧סַח הַ⁠זֶּ֛ה לַ⁠יהוָ֖ה בִּ⁠ירוּשָׁלִָֽם

(Some words not found in UHB: that/for/because/then/when if in,eight- teen year to/for=the_king Yoʼshiy^yāh/(Josiah) kept the,passover the=this to/for=YHWH in,Jerusalem )

If it would appear in your language that the author was making a statement and then contradicting it, you could reword this as a positive statement, combining verses 22 and 23. Alternate translation: [The only occasion on which the Israelites celebrated Passover during the whole time that the judges judged Israel and kings ruled in Israel and Judah was in the eighteenth year of King Josiah, when the people of Jerusalem observed Passover for Yahweh]

Note 2 topic: figures-of-speech / activepassive

נַעֲשָׂ֞ה הַ⁠פֶּ֧סַח הַ⁠זֶּ֛ה

(Some words not found in UHB: that/for/because/then/when if in,eight- teen year to/for=the_king Yoʼshiy^yāh/(Josiah) kept the,passover the=this to/for=YHWH in,Jerusalem )

The expression was done is a passive verbal form. If your language would not use that form, you could express the idea in active form or in another way that would be natural in your language. Alternate translation: [the people observed this Passover]