Mainly the SMS thing. As far as I can remember, when I reinstalled it on my new phone (about a year ago) I just had to verify my phone number via the SMS they s

Mainly the SMS thing. As far as I can remember, when I reinstalled it on my new phone (about a year ago) I just had to verify my phone number via the SMS they sent. Also, as I have already been using the Google Auth app, I was somewhat ignorant to check out Authy more in detail. Up to know I thought it wasn't using standard TOTP but some in-house developed algorithm by Twilio (or maybe a lesser known/less standard one) because SendGrid specifically tells you to use Authy. Which in itself seemed like a red flag.