FTPS (FTP with TLS) setup

We are trying to set up an FTPS connection to a server on the internet. It is not working because Zscaler is trying to proxy it and the TLS AUTH is not accepted (See FileZilla log below).
Anyone have any experience on how to get this to work in Zscaler?

|Status: Connecting to xxx.xxx.xxx.xxx:21…|
|Status:|Connection established, waiting for welcome message…|
|Response:|220 Zscaler/6.0: USER expected (Unix syntax)|
|Command:|AUTH TLS|
|Response:|503 Login with USER first|
|Command:|AUTH SSL|
|Response:|503 Login with USER first|
|Error:|Critical error: Could not connect to server|

Hi @jan.jong
Can you try implicit FTPS?
Or set a proxy inside the FTP client, if you are using explicit FTPS.

Either of that should work.