@hans swolfs Thanks for posting in our Q&A.
Based on my experience, Autopilot enrollment has User-Driven mode or Self-Deploying mode, there is no Self-driven mode.
For this error message, it is general and it is needed to analyse deeper logs to find the root cause. With Q&A limitation, it is better to create an online support ticket to get more accurate help. It is free. Here is the support link:
https://learn.microsoft.com/en-us/mem/get-support
Thanks for understanding.
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