https://www.gamespot.com/articles/destiny-2s-leviathan-raid-prestige-mode-delayed-he/1100-6453909/

Those getting ready for the Prestige version of Destiny 2's Leviathan Raid now have some extra time to make their preparations. Bungie has announced that the launch of the Prestige mode on PS4 and Xbox One has been delayed, due to the discovery of a serious bug.