Recursive calls not allowed - Deleting a directory

public RemovalOperationResult RemoveFiles(string path)
    {
        using (Session session = new Session())
        {
          session.Open(Config.FtpSessionOptions);
          return session.RemoveFiles(session.EscapeFileMask(path));
        }
    }
----------------------------------------------------
 RemoteDirectoryInfo rdi = ftpsSession.ListDirectory(ftpPath);
 foreach (RemoteFileInfo rfi in rdi.Files)
 {
    if (rfi.IsDirectory)
      {

         RemovalOperationResult ror;
         ror = ftpsSession.RemoveFiles(ftpPath + rfi.Name);
         if (ror.IsSuccess)
         {
         foreach (RemovalEventArgs removal in ror.Removals){
            log.Event("Removal of " + removal.FileName + " succeeded");
         }
     }
     else
     {
         log.Event("Removal failed.");
         return false;
     }

class FtpsSession
    {
public RemovalOperationResult RemoveFiles(string path)
    {
        using (WinSCP.Session session = new WinSCP.Session())
        {
          session.Open(Config.FtpSessionOptions);
          return session.RemoveFiles(session.EscapeFileMask(path));
        }
    } 
}