Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Hello Boštjan,
Please let the effective users try connect the network use the cellular data or home WiFi to try again.
Meanwhile, please click here to check if the connectivity works well: Confirm if the Outlook Connectivity has been checked under the Microsoft Office Outlook Connectivity Tests , click Next > fill the form (Note: we need check Use Autodiscover to detect server settings), click Perform Test. Please send us the entire result for further analysis. For privacy concern, I have sent you a Private Message to collect it. You can open your community profile and then click View private message to access it.
Regards,
Rudy