Why was martin luther excommunicated and declared a heretic answers?

Martin Luther was expelled by Pope Leo X on 3 January 1521 for blasphemy and disaffection, and for driving others off track from the teachings of the catholic church as Martin Luther's teachings were in light of the fact that he was attempting to conflict with the majority of the lessons of the Catholic church. He was given the opportunity to correct his view about the teachings but he did not an as such he was excommunicated.