That's odd, we use duo at work and it's great. Every user is configured to get a push notification directly to the device which bypasses the issues with SMS.
That requires the user to use the Duo app though, right?
I don't recall whether I had the option to use the app when I enabled MFA initially. However, after the fact, and as far as I can find, I cannot go back and enable the app.
That's correct, of course without having the app installed there is no option other than SMS or a hardware token.
I remember that configuring this is tricky, but I did eventually get user self enrollment configured with push being the default. Happy to dig more into my config, if you're curious: gabe@untapt.com
I don't recall whether I had the option to use the app when I enabled MFA initially. However, after the fact, and as far as I can find, I cannot go back and enable the app.