Powershell "local Admin"

$username = "XXXXX"     
$password = ConvertTo-SecureString "XXXXX" -AsPlainText -Force    
$logFile = "\\XXXXX\log\XXXXX.txt"  
Function Write-Log {
  param(
      [Parameter(Mandatory = $true)][string] $message,
      [Parameter(Mandatory = $false)]
      [ValidateSet("INFO","WARN","ERROR")]  
      [string] $level = "INFO"  
  )
    $timestamp = (Get-Date).toString("yyyy/MM/dd HH:mm:ss")  
   Add-Content -Path $logFile -Value "$timestamp [$level] - $message"  
}
Function Create-LocalAdmin {
    process {
      try {
        New-LocalUser "$username" -Password $password -PasswordNeverExpires -UserMayNotChangePassword -FullName "$username" -Description "local admin" -ErrorAction stop  
        Write-Log -message "$username local user crated"  
               Add-LocalGroupMember -Group "IT Systemadministratoren" -Member "$username" -ErrorAction stop  
        Write-Log -message "$username added to the local administrator group"  
      }catch{
        Write-log -message "Creating local account failed" -level "ERROR"  
      }
    }    
}
Write-Log -message "#########"  
Write-Log -message "$env:COMPUTERNAME - Create local admin account"  
Create-LocalAdmin
Write-Log -message "#########"