Hi @Xufyan Ali
According to the graph Api, by default, the calendar API returns the start and end times of an event in UTC, and provides the originalStartTimeZone and originalEndTimeZone properties to note the time zones used when the event was created.
Therefore, you can get the time zone of the shared calendar through the events
endpoint.
Here are my test results.
See the link below for details:
Hope this helps.
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