Hi Barış Bıkmaz,
Thank you for contacting Microsoft!
I attempted to reproduce the issue on my end and observed the same behavior. When sorting the drives in a SharePoint site by their name using the Microsoft Graph API, the results are consistently returned as an unsorted list.
Here are the API calls I used:
https://graph.microsoft.com/v1.0/sites/<site-id>/drives?$orderby=name
https://graph.microsoft.com/v1.0/sites/<site-id>/drives?$orderby=name ASC
https://graph.microsoft.com/v1.0/sites/<site-id>/drives?$orderby=name DESC
I recommend you raise a support case with Microsoft Graph, a Support Engineer will be able to look into this issue and assist you better. You can raise support ticket from New support request - Microsoft Entra admin center or https://admin.microsoft.com/#/support/requests.
Hope this helps.
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