@Sinetemba Fumbata , What i've tried is the following:
Delete all the files under the folder c:\Users<User>\AppData\Local\Packages\Microsoft.AAD.BrokerPlugin_cw5n1h2txyewy\AC\TokenBroker\Account
Then Reboot.
This made everything work as normal for me again.
Source: https://www.reddit.com/r/Office365/comments/xetxot/unresolvable_problem_on_signing_in_microsoft/