Hello, I've had MFA in use on Office365 E3 for about 18 months with the usual issues but here is one that has me stumped. I was setting up a new computer for him and installed Office Pro plus and authenticated once. Before shipping it out I went to open Word to be sure it was all set and it again asked for authentication and called my user to verify. The user answered the call and chose that he didn't initiate the authentication (why I don't know) and now his verification phone number won't accept calls or txt messages. I put my phone number in and still no calls or txts come through almost as if the new computer I'm initiating the MFA through has been banned. I had my CSP look at it and they had never seen anything like it. Anyone run into this before? The users Phone and old computer are working as if nothing is wrong.