Hi @Didier ,
Based on my analysis, I was able to replicate fetching events with -eq start/dateTime is not working as expected.
To get all the events which are scheduled for today, you can use below workaround to suffice your request.
Please use the below Graph API endpoint as an example.
https://graph.microsoft.com/v1.0/users/{user-Id}/events?$filter=**start/dateTime** ge '2021-12-21T00:00:00Z' and end/dateTime lt '2021-12-22T00:00:00Z'
- start/dateTime :-Please pass the today's date along with the time.
- end/dateTime :- Please pass the next day's date along with the time.
Hope this helps.
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