Hello there,
This might be due to system configuration differences or the version.
Also, make sure to check for User B's account status. To check a user’s account status, follow these steps:
Open the Azure portal and sign in as a Global Administrator.
Open the Azure Active Directory Extension by selecting All services at the top of the main left-hand navigation menu.
Type in “Azure Active Directory” in the filter search box and select the Azure Active Directory item.
Select Users and groups in the navigation menu.
Select All users.
Search for the user you are interested in and select the row to select.
Select Profile.
Under Settings ensure that Block sign-in is set to No.
Hope this resolves your Query !!
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