TLS/SSL Implicit error running from .Net Code, but can manually copy via GUI.

Try
    Dim sessionOptions As New SessionOptions
    With sessionOptions
        .Protocol = Protocol.Ftp
        .HostName = "hostName"
        .UserName = "UserName"
        .Password = "Password"
        .FtpSecure = FtpSecure.Implicit
        .TlsHostCertificateFingerprint = "FP"
    End With
 
    Using session As New Session
        session.SessionLogPath = "log.txt"
        session.DebugLogLevel = 2
        session.ExecutablePath = "C:\Program Files (x86)\WinSCP\WinSCP.exe"
        ' Connect
        session.Open(sessionOptions)
        ' Download files
        Dim transferOptions As New TransferOptions
        transferOptions.TransferMode = TransferMode.Binary
        transferOptions.ResumeSupport.State = TransferResumeSupportState.On
        Dim transferResult As TransferOperationResult = Nothing
        transferResult = session.PutFiles()
        ' Throw on any error
        If transferResult IsNot Nothing Then transferResult.Check()
    End Using
Catch ex As Exception
   MsgBox(ex.ToString)
End Try

session.ListDirectory("/some/path")

sessionOptions.AddRawSettings("SslSessionReuse", "0")