If your account has MFA, you need to use the app password instead of your regular password
1. Log in to Office 365.
2. Open the My account page:
3. On the Security & privacy tab, click Additional security verification to expand the available options and then click Create and manage app passwords. A new window will open.
Or go to: https://account.activedirectory.windowsazure.com/AppPasswords.aspx
4. While you're on the app passwords tab, click the create button.
5. Type name for remember where you use this password and click next.
6. In the next window, your app password will be displayed.
7. You can now use this app password when register connectors:
8. If you cannot create app passwords go to:
And make sure Allow users to create app passwords to sign in to non-browser apps option is selected