Start-ADTProcessAsUser question running as system / interactive admin

Hi all, i have a question regarding Start-ADTProcessAsUser.

For reference. I have a Script share only accessible to specific users / PC Accounts on my AD. In there my PSADT folder is located.

I also have a Scheduled task that runs the Invoke-AppDeployToolkit.ps1 as SYSTEM. (need it to rename the PC Account)

I also have a section that sets Windows Language/Culture/Region etc.. but it sometimes needs to run under the User context too. (Troubleshooting or re-applying the defaults)

For this is use Start-ADTProcessAsUser -FilePath "$env:SystemRoot\System32\WindowsPowerShell\v1.0\powershell.exe" -ArgumentList "-NoProfile -NonInteractive -ExecutionPolicy Bypass -File"$scriptPath""
-CreateNoWindow -WaitForChildProcesses -PassThru

The script is under a Path that can be accessed by the user of course.

If the script runs as system with the user logged in -> all good.

If i run it as Admin with the user logged in (throught the .exe or ps1) i get an error on the ProcessAsUser side.

What could cause this? how could i possibly fix this?

Thanks and BR

the error i get is: [Post-Install] :: Per-user region apply threw exception: Exception calling "LaunchAsync" with "1" argument(s): "Failed to retrieve an unelevated token for the calling account."

You could only get that from a Start-ADTProcess -UseUnelevatedToken call. I can't see how it would come from Start-ADTProcessAsUser.