Connection has been unexpectedly closed. Server sent command exit status 0, winscp with powershell

i am getting below error to automate the synchronization of files remote to local, please help on this error...
error:Connection has been unexpectedly closed. Server sent command exit status 0.

param (
$localPath = "xxxxx",
$remotePath = "xxxxx"
)

try
{# Load WinSCP .NET assembly
Add-Type -Path "C:\WinScp\winscp577automation\WinSCPnet.dll"

# Setup session options
$sessionOptions = New-Object WinSCP.SessionOptions -Property @{
Protocol = [WinSCP.Protocol]::Sftp
HostName = "xyz.com"
PortNumber=xxxx
UserName = "username"
Password = "password"
SshHostKeyFingerprint = "ssh-rsa 4096 xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
}

$session = New-Object WinSCP.Session

try
{
# Connect
$session.Open($sessionOptions)

# Synchronize files to local directory, collect results
$synchronizationResult = $session.SynchronizeDirectories(
[WinSCP.SynchronizationMode]::Local, $localPath, $remotePath, $False)

# Deliberately not calling $synchronizationResult.Check
# as that would abort our script on any error.
# We will find any error in the loop below
# (note that $synchronizationResult.Downloads is the only operation
# collection of SynchronizationResult that can contain any items,
# as we are not removing nor uploading anything)

# Iterate over every download
foreach ($download in $synchronizationResult.Downloads)
{
# Success or error?
if ($download.Error -eq $Null)
{
Write-Host ("Download of {0} succeeded, removing from source" -f
$download.FileName)
# Download succeeded, remove file from source
$removalResult = $session.RemoveFiles($session.EscapeFileMask($download.FileName))

if ($removalResult.IsSuccess)
{
Write-Host ("Removing of file {0} succeeded" -f
$download.FileName)
}
else
{
Write-Host ("Removing of file {0} failed" -f
$download.FileName)
}
}
else
{
Write-Host ("Download of {0} failed: {1}" -f
$download.FileName, $download.Error.Message)
}
}
}
finally
{
# Disconnect, clean up
$session.Dispose()
}

exit 0
}
catch [Exception]
{
Write-Host ("Error: {0}" -f $_.Exception.Message)
exit 1
}

Please attach a full session log file showing the problem (using the latest version of WinSCP).