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Date & Time: n/a
Frequency: 100% repeatable
World name: Siren
Character name: Gelee Kaine
Retainer name: n/a
NPC name: Baderon
Monster name: n/a
Class/Level: 90 BRD
Party or solo: solo
In-game time: n/a
Area and coordinates: The Drowning Wench, Limsa Lominsa
Housing: n/a
Steps:
1. Play ARR New game plus, Part 1. Get up to Call of the Sea where you need to talk to Baderon.
2. Talk to Baderon and attempt to click complete on the dialog box.
3. Error that is returned is as follows:

"Unable to interrupt New Game+ mode from your current location. Please try again from a different location."

Further investigation reveals the following:

If you are close to the bar and the NPC (proximity) you also receive the same error message when attempting to suspend NG+.

If you stand away from the NPC you can suspend NG+.

You must stand at the maximum interact distance to still trigger Baderon and then you can successfully complete the quest.

This suggests that there is an invisible flagged area directly around the NPC / bar interefering with the quest progression here.