Hi @Jackie Dinh
Welcome to Microsoft Q&A Forum.
I understand how frustrating these kinds of issues can be, and I truly appreciate you taking the time to describe your scenario.
Based on Microsoft documentation and community experience, brief delays after changes, such as adding or removing users, are expected in large-scale cloud systems like Microsoft Entra ID. These delays are by design to ensure consistency and reliability across distributed servers. It is acknowledged that short sync delays (a few seconds to minutes) are normal in such environments.
To work around this, please try the following: after adding UserB, wait 5-10s before retrieving the member list.
However, accessibility and user experience remain top priorities, and feedback like yours is essential to improving the platform. I strongly encourage you to share your input on the Microsoft Feedback Portal so the product team can review and consider your experience.
I truly appreciate your patience and understanding. If you need any more clarification, please don’t hesitate to ask, I’m here to assist however I can.
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