I'm not sure exactly what you mean by "password also reset have access to account", so I'll throw this out there. I've seen this same thing happen for new accounts that try to log into OWA for Exchange Online when the user has not first logged
into MSO via the home.microsoftonline.com website or the SSO application and reset the account's password before opening OWA. The problem is that a user must first log into one of those options first after their account has been created or their password has
been reset, because MSO requires that they change their password again before they can access the sites within the service. If you've reset the accounts' passwords through the MSO Admin site and each user has not reset the account's password to something else,
they will first need to do that before they can access OWA using the account, you can't override that through the Admin site.
If you're already doing that, then I would recommend submitting a support ticket to MSO and request assistance with these accounts.
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