> 2021-11-04 12:17:23.025 EPRT |2|fe80:0000:0000:0000:48f4:bde2:c473:a484|53686|
< 2021-11-04 12:17:23.025 500 Bad EPRT protocol.
The above means that for WinSCP, it's IPv6 connection, so WinSCP has to use
EPRT, instead of
PORT. But the vsftpd server sees the connection as IPv4. That can happen if the network between you and the server changes between IPv4 and IPv6. The solution is not to use the active mode in the first place. Or are you able to use the active mode with any other FTP client?