Use task scheduler to trigger Alteryx when computer is locked with Powershell

I am looking to run an Alteryx file with powershell through task scheduler in Windows 10. I have everything working, when the computer is unlocked, since I can send keys, however when the computer locks, sendkeys does not work and my script fails.

Since I want to run the file early in the morning, I need this to work when computer is locked. Any help would be appreciated.

start-Process -Filepath "filepath.yxmd"
sleep - s 60
$obj = New-Object -com Wscript.Shell
sleep - s 3
$obj.sendkeys("^{r}")

It is a bummer cause Alteryx want users to pay more money to schedule files...