@Moncef BRIGHACH, thanks for sharing the solution. As you can't mark your own reply as answer, to help others who have the same issue to find the solution quickly, please let me write a summary:
Issue:
Microsoft SSO Plugin for macOS is working great. However, the Company Portal app notifications asking the user to register his device with Intune keeps prompting.
Resolution:
Thanks for your time and have a nice day!
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