Starting August 11th, 2017, we will use Google Authenticator as our 2FA app. Authy will no longer be available as a 2FA option for new customers that registered after 10th August 20:10 JST. We plan to migrate completely from Authy to GA in a months’ time.
All existing customers need to update their security settings to GA to avoid login issues. See how to do it here: How do I change my 2FA app from Authy to Google Authenticator?
For new customers who have registered for an account after 10th August 20:10 JST, you will now use Google Authenticator (GA) as your 2FA. This should be set up right after registration: How do I set up 2-factor authentication?