We keep getting "Failed to login to Apple" error while using Autoconfiguration tool. And then another window appears, which says "Your Apple ID is being used to sign in to a new device." What's wrong?
It seems that you have a two-factor authentication enabled for your Apple Developer account. In order for the Autoconfiguration tool to work, please disable TFA, use the tool and then enable it again.
Alternatively, you can configure iOS platform manually. To do so, please follow the guide: http://docs.pushwoosh.com/docs/apns-configuration