When I log in to https://nianticlabs.com/reserve-nianticid using the same Google account as I use in Ingress I get the message:
"Niantic ID Reservation
No codenames found. Please log out and try a different account."
I'm closing this because it's not an Ingress bug.
Please see https://community.ingress.com/en/discussion/comment/156691/#Comment_156691 for more information.