ssh2-sftp-client: client sftp exists crash

when i call exists function with path folder not existing. i have error :

stack:"Error: sftp.exists: sftp.realPath: 
Cannot find message [/Inbox/tip/test] /Inbox/tip/test\n 
at formatError (\node_modules\ssh2-sftp-client\src\index.js:56:10)\n    
at SftpClient.exists (\node_modules\ssh2-sftp-client\src\index.js:241:27)\n    
at process._tickCallback (internal/process/next_tick.js:68:7)"

my code :

 clientSftp.connect({
        host: ssh2.host,
        port: ssh2.port,
        username: ssh2.username,
        password: ssh2.password
      }) .then(() => {
        const folder = `${ssh2.path}/${type}`;
        return clientSftp.exists(folder);
      }) .then((exist) => {
          return resolve(exist);
      }).catch(err => {
          self.logger.error( `transport to ${localFile}/${remoteFile} error`+ err.message);
          return reject(err);
        });