How to disable passive mode in linux ftp command

I am using the "ftp" command of linux to send data to a 3rd party provider. This company states that we need to "Disable passive mode in your FTP client", and I confirm it doesn't work in passive mode.

However, when I googled the linux command, I see that the "-p" flag is "the default now for all clients (ftp and pftp) due to security concerns using the PORT transfer mode. The flag is kept for compatibility only and has no effect anymore."

How do I disable passive mode then? And, is it that bad?

Once you have logged into the site with FTP, type passive and then do your transfer.

Just run passive within the client.

Passive mode changes the method used for connecting to the FTP, as active mode often encounters issues with more restrictive firewall rules.

in ftp linux commad client type: passive n

For those we use WinSCP you can disable Passive flag. Edit -> Advanced:

Also, if you are using docker container check if there is a "public host" variable. In case of stilliard/docker-pure-ftpd there is PUBLISHOST:

-P $PUBLICHOST # IP/Host setting for PASV support, passed in your the PUBLICHOST env var