Hi Koala2861
Thank you for posting your question in the Microsoft Q&A forum.
Based on your description that your Outlook application is functioning correctly. The issue stems from the specific button your clients are clicking when they accept the invite.
Please note that your Outlook calendar can only update to "Accepted" if it receives a digital receipt from the client. It appears these specific clients are selecting the option "Do not send a response" or uncheck the "Email organizer" box. When they choose this, the meeting goes onto their calendar, but the acceptance message will not come through, and your Outlook cannot receive the signal to change the status from "No Response" to "Accepted".
Since this is a client-side action, I recommend sending a quick note to the clients who frequently do this to ask them to please ensure they click "Send Response Now" or check the "Email organizer" box.
For Window devices:
For MacOs devices: (click to edit RSVP to edit response)
I hope this clarifies the situation! If you have any further questions, please feel free to let me know.
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