Blizzard have announced that players that manage to get Keystone Master now will not be receiving the Draconic Mark of Mastery until they fix some issues with it. Once the problems are resolved players will receive it retroactively.
Keystone Master (Source)
In order to address a bug, we have disabled a part of Keystone Master.
At this time, players will not get the Draconic Mark of Mastery from completing Keystone Master. Once we re-enable it, the fix will be retroactive.
Thank you for your patience and understanding.
