Originally Posted by CPH-Flyer

What exact ticket did you book?

If you booked a domestic flight in Japan, or a flight from Japan to somewhere, then yes the website reroutes you to the Japan region website. You'll discover that most airlines do this. Some with more warning than other.

If you booked.a flight originating in the US this would be rater surprising, and I'd reach out to NH to ask them why that happened.