Brahma basically refused his ask for and defined to him that everybody ought to die sooner or later. He himself doesn't have the boon of mortality so how wouldn't it be doable for him to bless Mahishasura with that. Mahisasura, discouraged to hear this, considered deeply for a while https://lorenzopaitb.jiliblog.com/77095097/the-ultimate-guide-to-maa-durga