Hi thanks for posting here in Microsoft community, at what exact step does the login fail? and message shows up on the screen?
What you can try is signing in from a different network, sometimes Microsoft blocks login because of a vpn or mobile hotspot, try to switch from WiFi to mobile data also if you have vpn / proxy try to turn it off and use a different device on a different network.
I hope that helps you, let me know how it goes.
Chard