Not Getting extension of msg attachment

I have Loaded .msg File to aspose mail message message to save it into eml using
message = MailMessage.Load(FilePath);
message.Save(memoryStream, SaveOptions.DefaultEml);

But if there is .msg attachment in MSG File after loading it into mail message, I m unable to get attachment extension (Original Attachment Filename = msgattachment.msg after loading its is “msgattchment” without extension ) due to which the file is unable to open .

Kindly provide a solution for the same.

@SRCCC

Could you please share your MSG file along with complete code example to reproduce the same issue at our end? We will then provide you more information on it.