Azure VM Managed Run Command – RunAsUser and RunAsPassword arguments are ignored

I’m trying to execute a powershell script through the managed run commands.
It is working as expected, but when I add RunAsUser and RunAsPassword arguments as documented here, these arguments are ignored and the script still executes as systemprofile user.
I verified, the specified user has Virtual Machine Administrator Login role, so it has access to the VM and to any location on this one.
Am I missing something?