So... Shinwa has decided for me to do a Carl quest to obtain a piece of her bracelet

Problem is... I can't do Carl? I get an error: Oh No! Oh, no! Apparently you haven't quite worked out how to get to the Omen Islands yet! I suppose you probably need to put together an unknown map!

I've never had her ask for me to do a Carl quest before... I just wanted to do Shinwa for the first time in months... ;-; Will her quest reset or something? I haven't been on in months. Not sure how to open Carl quests either.

Her quests reset every night at midnight (12:00am) Subeta time.

Carl is on Omen Islands. You need access to that area to do this quests.

Here is a list of all the pieces. You need all nine to access the island. You can track which pieces you have (they need to be in your inventory) on the Treasure Maps page.

Strange that Shinwa would send you there though. I thought she didn't send users to Carl unless they had access to him.