Hi , @KasperJ90
According to the message 'The session ID cannot be found. Either the session does not exist or it has already expired', seems like when you do not use analyze in excel for some time, the session would be expoired. After closing this message, it would be 're-connected'.
See this similar note:Token expired error
Troubleshoot the connection from Excel to Power BI data - Power BI | Microsoft Learn
If you receive a token expired error, it means you haven't recently used the Analyze in Excel feature on the computer you're using. Simply re-enter your credentials, or reopen the file, and the error should go away.
Thank you for your time and sharing, and thank you for your support and understanding of PowerBI!
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