You are to convene at the Seat of the Lord Commander to discuss how to reach Azys Lla without the key.

Requirements

This quest is available if you have completed the quest One Good Turn.

Starting the Quest

Talk to Alphinaud in Ishgard to begin the quest.

Speak with Aymeric

Go north and use the Aethernet Shard to go to the Forgotten Knight Aethernet Shard. Go east from there and through the double doors behind Firmalbert. Talk to the Temple Knight Guard and say Yes to proceed. Talk to Aymeric and there will be a cutscene.

Speak with Tataru

Go outside and turn left, and enter the Forgotten Knight. Go downstairs and talk to Tataru to complete the quest.

Next Main Scenario Quest

After you complete the quest, talk to Tataru to accept the next quest: Aetherial Trail.