I recently set up a client with a new Office 365 Business Premium package, using Azure/Office sign-in on all their client desktop systems. While setting this up, as I added each user account to a client desktop system, it requested that it verify my identity with a text message sent to a mobile phone, and as I was setting this all up by myself without the users nearby, I used my mobile number in each case. So it now transpires that every user account now has my mobile number permanently attached to it, and there doesn't appear to be a way to change this? The users are trying to set up their accounts on other devices, and I'm far away on another job with my mobile phone buzzing away with verification codes!
Surely there must be a way of changing this mobile number for each user? Ideally from the global administrators account so we can do it all at once?