- I receive the error "You can't do that right now" when using the Dalaran Hearthstone.
- I talked to Amisi Azuregaze to pick up the Dalaran Hearthstone, and now it won't let me use it.
To be able to use your Dalaran Hearthstone, you need to complete the Legion introductory questline on this character. Visit the Hero's Call Board in Stormwind or the Warchief's Command Board in Orgrimmar and pick up the Broken Shore option "Fight The Legion". This will grant you the quest The Legion Returns (Alliance/Horde).
If you have already done this questline on another character on the account, Recruiter Lee (Alliance) or Holgar Stormaxe (Horde) will give you a choice to skip it. If you choose to skip, you will be immediately teleported to Dalaran and you will be asked to hand in the last quest - In the Blink of an Eye. Turn in this quest to unlock your Dalaran Hearthstone.