Hi, @Pall Piars
Thank you for posting in Microsoft Q&A forum.
Ensure the DP server meets all prerequisites for SCCM, including supported OS versions and roles/features.
Confirm network connectivity between the SCCM site server and the DP.
If the issue persists, consider removing the DP role and reinstalling it.
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After the way you tag questions on Q&A is updated, for any "Microsoft Configuration Manager" related problem, you can tag it with "Microsoft Intune", and then "Microsoft Configuration Manager" as the child tag.