I have created an app in azure AD, in my company tenant. In application permissions, I have added Calendars.Read and Calendars.ReadWrite (Read and write calendars in all mailboxes) with application permission type, and I have grant admin consent.
In users, I have added user with personal Microsoft account (outlook.com) as a guest user.
When I am calling a graph for Member users, I am able to receive calendar events (and create a new ones), but when I am calling a graph for a Guest users I get exception MailboxNotEnabledForRESTAPI. Message: REST API is not yet supported for this mailbox.
Is there some limitation that I can create event only to a Member user, or I have miss-configured something?