2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/109111In this paper, congruences between holomorphic Hilbert modular forms are studied. We show the best possible level optimization result outside l for l > 2 by solving the remaining case of Mazur principle when the degree of the totally real field is even.This is the newest version of a preprint by the author with the same title (this paper is already submitted to a journal)Number Theory11F33; 11F80; 11G18text