Hi,
>>But she has also given permissions to another inbox to manage the room.
How did she give permissions to another user to manage the room? Did you do it in Outlook via Account Settings > Delegate Access? If this is the case, please make sure that the "My delegates only" option is selected for the "Deliver meeting
requests addressed to me and responses to meeting requests where I am the organizer to:" option.

If I've misunderstood something, please feel free to let me know.
Regards,
Steve Fan
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