WP_FAIL2BAN_PROXIES not working (empty proxy IP list)


I’m facing an issue using WP_FAIL2BAN_PROXIES.

My wordpress is behind a loadbalancer and I’m only seeing loadbalancer’s IP’s in my auth.log (172.19.X.X)

I’ve added following line in my wp-config.php:
define(‘WP_FAIL2BAN_PROXIES’, [‘’]);

Unfortunatly, it doesn’t work.
Loadbalancer’s IP still appears in my auth.log and proxy IP list is empty in wp-fail2ban setting page.

Technical informations:
Debian 9.9
Wordpress 5.1.8
WP fail2ban 4.3.0