Cannot convert argument "sessionOptions"

We keep getting the following error when trying to download files from a FTP host with a PS1 script.
I've attached the script(FTP.txt) and I've also tried to use the following script with our credentials: https://winscp.net/eng/docs/script_download_most_recent_file#powershell

Able to login with the WinSCP client and get the files manually.

We do not provide a support for 3rd party "WinSCP PowerShell Wrapper Module" here.
Please go to:
https://github.com/tomohulk/WinSCP