PowerShell email function

Hi  , 

I try to create a sent mail function which will be use by some looping code ,  it was written in PowerShell code as below  , which when i fire the logic in PowerShell ISE , the body message and Email subject where i receive do not have value

function SendOutlookMail([string]$EmailTo , [string]$EmailSubject ,  [string]$BodyMessageLine1)
{

$Outlook = New-Object -ComObject Outlook.Application
$Mail = $Outlook.CreateItem(0)
$Mail.To = $EmailTo
$Mail.Subject = $EmailSubject
$Mail.Body = $BodyMessageLine1
$Mail.Send()
$Outlook.Quit()

}
# call the function and pass in value to sent mail
SendOutlookMail("Some1@email.com" , "Email Subject" , "Body Message")

if i hard code the value by updating this 2 line , everything work fine , where my receive mail body and subject got value

$Mail.Subject = "Email Subject"
$Mail.Body =  "Body Message"

what is going on ?