Bosses aren’t awarding fragments in the raid.
Bungie’s Destiny: Rise of Iron is facing a pretty serious bug right now. In the Wrath of the Machine raid, players can receive SIVA Key Fragments which combine to form a Cache Key. These keys can be used for additional loot drops in encounters but the most important part is the ability to farm Key Fragments even if you’ve done the raid.
With its latest hotfix, Bungie reduced the amount of Key Fragments that could be awarded with each raid completion until the next reset. However, instead of SIVA Key Fragements and Keys going missing from one’s inventory, some players are now not receiving any Key Fragments as boss drops.
Considering the raid is one’s best option to obtain Light level 400 gear at Heroic, not to mention a chance at some of the cooler weapons in the game, the lack of Key Fragments is denying some players the additional loot. Bungie is currently investigating the issue but there’s no indication as to when it will be fixed. Stay tuned for more information in the meantime.