The Elder Scrolls Online: Tamriel Unlimited

The Dragonguard quest is the last of 6 quests in the main storyline of the Dragonhold expansion. Please note that if you did not take the next task immediately after completing the previous task, you can then receive it from Sidur, at the docks of the Sanctuary of the Dragon Guard. However, the indication that he has tasks for you does not always work. So if you have completed the task and don’t know what to do next, try talking to him.