Hi @Jussi Lehti ,
Can you provide me with the ULS Log of your error?
- Download the ULS Viewer tool to your SharePoint web front-end server.
- Open the ULS Viewer application. Click the "File" menu >> "Open from File >>". This will open the default LOGS folder of the SharePoint hive "C:\Program Files\Common Files\microsoft shared\Web Server Extensions\16\LOGS".
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