@Kevin Sutherland Thanks for your update.
1.Assign intune license to the target user that you want to do enrollment.
https://learn.microsoft.com/en-us/mem/intune/fundamentals/licenses-assign
2.Use a local account to sign in this device. The easiest enrollment method is Open the Settings app > Accounts > Access work or school > Connect, select Join this device to Azure Active Directory, and enter the user that has an intune license and enter the information they're asked.
3.When the process is finished, please check if this device exists in intune portal and MDM shows "intune". If yes, it means this device is enrolled successfully.
Hope it will help.
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