A cloud-based identity and access management service for securing user authentication and resource access
Hi @Fernando Sanchez ,
I am able to replicate your issue if no license is assigned to the user account which is calling /calendar endpoint. Please assign a valid license that will give you access to the office 356 apps. Refer this for more details https://learn.microsoft.com/en-us/microsoft-365/commerce/licenses/subscriptions-and-licenses?view=o365-worldwide
Hope this helps.
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