Hi @Laura MacKellar
Welcome to our forum!
Looks like your issue is more related to Microsoft Booking, please kindly understand that the Outlook tag here we mainly focus on general issues about Outlook desktop client. In order to better solve your problem, it's suggested that you could post your case in dedicated forum for Microsoft Booking for more professional advice.
Based on my research, you could display your work time on the bookings by the steps: Calendar>Drop-down triangle next to New Event>Bookable time>Change availability, type necessary information> Create, you could get a bookable time displayed as below:
In addition, as i know, if others can't see your availability, they may not be from the same organization as you, please refer to the article to learn more: Can't see scheduling or free/busy information for meeting attendees - Microsoft Support
Hope it helps!
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