Hi @abm,
yes. But unfortunatelly I wasn´t able to change the language. I do not find the setting 😞
The Flow is split into two parts now.
In the first part the run gets triggered by a button and the file gets attached. The second step is not important and could be skipped. The metadata of an existing xlsx-file gets loaded. In the third step the same file gets updated with the content of the xlsx-file from the button trigger. The last step starts the second Flow to upload the data in Dynamics 365.

The second Flow also gets triggered by a button. But this should by skiped if the first flow starts the second one.
The datasets from the xlsx-file gets inquired.
For testing purposes I´ve changed the next step. Instead of loading up to D365 I´m creating a notification.

The error message occures in the first Flow in the step of updating the existing file:

Body:
"message": "The file https://XXX.com/XX/XX/XX/FLOW_UPLOAD.xlsx is locked for shared use by XX.XX@XXX.com [membership].\r\nclientRequestId: c7d11001-42f5-4f45-8a2a-8e4461f8690e\r\nserviceRequestId: d1ef2d9f-90ca-a000-7c2d-80fd6773cb46;d1ef2d9f-80ce-a000-7c2d-809fd0ec4003", "status": 423
The user XX.XX@XXX.com is my user account.
Thanks in advance
Chris