I received the email from Apple:
In an effort to keep your account more secure, two-factor authentication will be required to sign in to your Apple Developer account and Certificates, Identifiers & Profiles starting February 27, 2019. This extra layer of security for your Apple ID helps ensure that you’re the only person who can access your account. If you haven’t already enabled two-factor authentication for your Apple ID, please learn more and update your security settings.
I remember I had to turn off 2-factor authentication in order to finish my build process on expo the first time. Does expo nows support 2-factor authentication?