Stuck on "In a Titan Spot"

I'm at the stage where I attune to the aetheryte in U'Ghamaro Mines. I've attunded multiple times every time I do it says Quest complete - The Navel Hardmode now accessible. However, the quest doesn't go away. It stays at the same point, and I cannot access The Navel Hardmode through the duty finder.

Typically this is caused by having a full inventory. Clear a space and try again?

Got it, thanks!