I believe there is a problem with the desktop app so this is what I did and it worked:
1. Open desktop MiUnlock app and proceed to the sms verification step, leave the app open.
2. Open the file 'config/app.info' and copy the url from "account_login_url" on your browser.
3. On the browser proceed to the sms verification step. When you do this you should receive the sms!!
4. Go back to the desktop MiUnlock app and use the code!
It has to be done on that order otherwise it will not work or it will, I didn't test it.
I hope this work for you guys
