By default NextAuth authenticates the domain provided by the NEXTAUTH_URL environmental variable and if it is on a sub domain like www.example.org also all domains below www like subdomain.www.example.org or subdomain.subdomain.example.org. It is often smart to make the domain authentication work across all sub domains to avoid restrains when branching out API services or deploying on sub domains. To do this you need to set the cookie domain to root wildcard. If my web app is deployed on http...
