Hi,
Thanks for posting in Microsoft Q&A forum.
As you mentioned that the task sequence ran successfully, maybe we could first check the disk of the device.
We could boot up into WinPE and open the Command Prompt, run command to check whether the system partitions and volumes are correct.
For more information, we could refer to this link:
https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/diskpart
What's more, I found there is someone met the similar issue and fixed it, please check:
https://social.technet.microsoft.com/Forums/ie/en-US/6b5b5140-3a92-4d87-9508-93fc8bddee5d/win10-prestage-boot-device-not-found?forum=configmanagerosd
And the article he referred to is in this link:
https://techcommunity.microsoft.com/t5/configuration-manager-archive/how-to-apply-task-sequence-prestaged-media-on-multi-partitioned/ba-p/392239
Hope the above information can help you.
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