Received unexpected end-of-file from SFTP server

Hello,
I am trying to connect my VPS through Filezilla but when I goes to connect then I am getting this error:
Status: Connecting to xx.xx.xx.xx…
Response: fzSftp started, protocol_version=8
Command: keyfile “/home/mycomp/Desktop/id_rsa2b21”
Command: open “root@xx.xx.xx.xx” 22
Command: Pass: ****************************
Error: Received unexpected end-of-file from SFTP server
Error: Could not connect to server
I need help for resolving this error.
I am appreciating for any help to resolve this error.
Thanks

Hello,
Sorry for this, I forgot to read this info before continuing:

Now, I have successfully connected to filezilla through FTP.
Thanks