Dear James Byrne,
Thanks for posting in Microsoft Community.
Based on your description, you said that customers are still getting the option to manage their appointment and you want to restrict them to do so. Before moving forward, we need more detailed information about the situation you are experiencing.
Kindly share with us the information below:
Have you tried it by deactivating the Default scheduling options?
Have you tried redoing the previous settings to see if it works?
Based on your screenshot, it appears that the toggle is in the off position, as you want; how did it appear previously?
As far as I know, your customer may always change their booking after receiving the confirmation email. That email contains a link to a website where they may create a new booking, reschedule, or cancel it.
For more, refer to:
We look forward to your response. Thanks for your cooperation.
Sincerely,
De Paul | Microsoft Community Moderator
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