ProFTPD options: how to debug

Question

Within a Red Hat Enterprise Linux Server release 7.6 (Maipo) I would like to use the module mod_ban in order to set a ClientConnectRate event. The service is started as: systemctl start proftpd

Service is configured as below:

[root@lclftpcrb001blq ~]# cat /usr/lib/systemd/system/proftpd.service
[Unit]
Description = ProFTPD FTP Server
After = network.target nss-lookup.target local-fs.target remote-fs.target

[Service]
Type = forking
PIDFile = /run/proftpd/proftpd.pid
Environment = PROFTPD_OPTIONS=
EnvironmentFile = -/etc/sysconfig/proftpd
ExecStart = /usr/sbin/proftpd $PROFTPD_OPTIONS
ExecReload = /bin/kill -HUP $MAINPID

[Install]
WantedBy = multi-user.target

So, other than configuring this code in /etc/proftpd.conf:

<IfDefine DYNAMIC_BAN_LISTS>
  BanEngine     on
  BanLog        /var/log/proftpd/ban.log
  BanTable      /var/run/proftpd/ban.tab
  BanOnEvent  ClientConnectRate   10/00:10:00 00:15:00 "Stop connecting frequently"
  BanMessage                    "Host %a has been banned"
  BanControlsACLs               all allow user ftpadm
</IfDefine>

I also have /etc/sysconfig/proftpd:

PROFTPD_OPTIONS="-DDYNAMIC_BAN_LISTS"

Despite the configurations, when I start the service the debug tells me:

proftpd[29035]: <IfDefine>: skipping 'DYNAMIC_BAN_LISTS' section at line 85

From my understanding, the IfDefine block is loaded if DYNAMIC_BAN_LISTS is present in /etc/sysconfig/proftpd. So the only thing I can think is that for some reason it's not retrieving the option from /etc/sysconfig/proftpd ...

How can I check this point?

Thanks!