What is a valid PowerShell parameter entry?

Hi Expert,

What is a valid parameter for LocalAccountNames and Local Account, this script doesn't work properly? Can you tell what's missing?

Thank you.

Param
(
      [Parameter(Position=0,Mandatory=$false)]
      [ValidateNotNullorEmpty()]
      [Alias('cn')][String[]]$ComputerName=$Env:COMPUTERNAME,
      [Parameter(Position=1,Mandatory=$false)]
      [Alias('un')][String[]]$AccountName,
      [Parameter(Position=2,Mandatory=$false)]
      [Alias('cred')][System.Management.Automation.PsCredential]$Credential
)
      
$Obj = @()

Foreach($Computer in $ComputerName)
{
      If($Credential)
      {
            $AllLocalAccounts = Get-WmiObject -Class Win32_UserAccount -Namespace "root\cimv2" `
            -Filter "LocalAccount='$True'" -ComputerName $Computer -Credential $Credential -ErrorAction Stop
      }
      else
      {
            $AllLocalAccounts = Get-WmiObject -Class Win32_UserAccount -Namespace "root\cimv2" `
            -Filter "LocalAccount='$True'" -ComputerName $Computer -ErrorAction Stop
      }
      
      Foreach($LocalAccount in $AllLocalAccounts)
      {
            
        Set-ExecutionPolicy remotesigned -Force
        Import-Module activedirectory

        $Object = New-Object -TypeName PSObject
            
            $Object|Add-Member -MemberType NoteProperty -Name "Name" -Value $LocalAccount.Name
            $Object|Add-Member -MemberType NoteProperty -Name "Full Name" -Value $LocalAccount.FullName
            $Object|Add-Member -MemberType NoteProperty -Name "Caption" -Value $LocalAccount.Caption
                  $Object|Add-Member -MemberType NoteProperty -Name "Disabled" -Value $LocalAccount.Disabled
            $Object|Add-Member -MemberType NoteProperty -Name "Status" -Value $LocalAccount.Status
            $Object|Add-Member -MemberType NoteProperty -Name "LockOut" -Value $LocalAccount.LockOut
            $Object|Add-Member -MemberType NoteProperty -Name "Password Changeable" -Value $LocalAccount.PasswordChangeable
            $Object|Add-Member -MemberType NoteProperty -Name "Password Expires" -Value $LocalAccount.PasswordExpires
            $Object|Add-Member -MemberType NoteProperty -Name "Password Required" -Value $LocalAccount.PasswordRequired
            $Object|Add-Member -MemberType NoteProperty -Name "SID" -Value $LocalAccount.SID
            $Object|Add-Member -MemberType NoteProperty -Name "SID Type" -Value $LocalAccount.SIDType
            $Object|Add-Member -MemberType NoteProperty -Name "Account Type" -Value $LocalAccount.AccountType
            $Object|Add-Member -MemberType NoteProperty -Name "Domain" -Value $LocalAccount.Domain
            $Object|Add-Member -MemberType NoteProperty -Name "Description" -Value $LocalAccount.Description
            
            $Obj+=$Object
      }
      
      If($AccountName)
      {
            Foreach($Account in $AccountName)
            {
                  $Obj|Where-Object{$psitem.Name -like "$Account"}
            }
      }
      else
      {
            $Obj
      }
}