I did try to setup my FTP server using Synology NAS DS216j with latest DSM version or FileZilla FTP Server which sit behind TP Link AX90 (AX6600) Wifi router which connected in Bridge mode to ONU unit (Fibre optic media).

I did connect using FileZilla FTP client in local IP address which was in the same sub net. It works good no problem at all. But when I try to connect outside this network. It can't connect. The problem is below

Error:    GnuTLS error -15: An unexpected TLS packet was received.
Error:    The data connection could not be established: ECONNABORTED - Connection aborted

This occurred are the same when I use Synology NAS or FileZilla FTP server. I think the problem caused from Port forwarding setting in TP Link.

Please suggest properly setting for my setup. My Wifi router got public IP address and I use DDNS dot net service and Synology DDNS. It resolve right public IP address which show on my wifi router.

Thank you very much.

Pornchai POP