How to stop hourly reverse DNS queries (PTR in query log)

[csh]

How do stop pihole making PTR queries every hour?
Exactly 254 PTR queries - scans entire subnet.

Search returned these topics, but all are closed:

Pi-hole Reverse DNS queries every hour

The change is that with the most recent version, we also try to get host names for devices in your network which are not actively using Pi-hole. Assuming your devices made only (or at least mostly) queries over IPv4 to your Pi-hole, we haven't tried to resolve their IPv6 host names before. We're already looking into this. The issue itself comes from the growing number of temporary IPv6 addresses being enabled by default in Windows and Mac (if I recall correctly). My proposed solution is to add …

Excessive number of PTR entries in the query log

That's reasonable and the log does indicate that each host seems to be queried once per hour, but my query log seems to be inundated with PTR queries. Is there any way to filter them out?

According to the documentation this behaviour can be adjusted via the /etc/pihole/pihole-FTL.conf file:

Configuration - Pi-hole documentation

REFRESH_HOSTNAMES=NONE

I put it into the /etc/pihole/pihole-FTL.conf, and restarted the container with no change.
Later also in the setupVars.conf (found in one of the topics listed), again no luck
I do have about 15 local IPs listed in Local DNS Records to be able to see the names instead of IPs in the dashboard.

Docker installation, latest version.
Here is my config:

pihole version
 Pi-hole version is v5.5 (Latest: v5.5)
 AdminLTE version is v5.7 (Latest: v5.7)
 FTL version is v5.10.2 (Latest: v5.10.2)

cat /etc/hosts
127.0.0.1	localhost
::1	localhost ip6-localhost ip6-loopback
fe00::0	ip6-localnet
ff00::0	ip6-mcastprefix
ff02::1	ip6-allnodes
ff02::2	ip6-allrouters
172.20.0.4	cc57f5911625

cat /etc/resolv.conf 
search lan
nameserver 127.0.0.11
options ndots:0

grep REFRESH_HOSTNAMES *.conf
pihole-FTL.conf:REFRESH_HOSTNAMES=NONE
setupVars.conf:REFRESH_HOSTNAMES=NONE

cat pihole-FTL.conf
REFRESH_HOSTNAMES=NONE
REPLY_ADDR4=0.0.0.0

cat setupVars.conf
BLOCKING_ENABLED=true
LIGHTTPD_ENABLED=
IPV6_ADDRESS=
CONDITIONAL_FORWARDING=
CONDITIONAL_FORWARDING_IP=
CONDITIONAL_FORWARDING_DOMAIN=
CONDITIONAL_FORWARDING_REVERSE=
WEBPASSWORD= removed
ADMIN_EMAIL=
WEBUIBOXEDLAYOUT=boxed
WEBTHEME=default-light
DNSMASQ_LISTENING=single
PIHOLE_DNS_1=1.1.1.1
PIHOLE_DNS_2=1.0.0.1
DNS_FQDN_REQUIRED=false
DNS_BOGUS_PRIV=true
DNSSEC=false
REV_SERVER=false
IPV4_ADDRESS=0.0.0.0
REFRESH_HOSTNAMES=NONE
INSTALL_WEB_SERVER=true
INSTALL_WEB_INTERFACE=true
PIHOLE_INTERFACE=eth0
QUERY_LOGGING=true

grep PTR /var/log/pihole-FTL.log 
[2021-10-01 22:08:03.512 326M]    PIHOLE_PTR: internal PTR generation enabled (pi.hole)
[2021-10-01 22:08:03.814 416M]    PIHOLE_PTR: internal PTR generation enabled (pi.hole)
[2021-10-01 22:08:04.811 454M]    PIHOLE_PTR: internal PTR generation enabled (pi.hole)

grep PTR /var/log/pihole.log

Oct  2 08:55:45 dnsmasq[454]: query[PTR] 1.1.168.192.in-addr.arpa from 192.168.1.101
Oct  2 08:55:45 dnsmasq[454]: query[PTR] 2.1.168.192.in-addr.arpa from 192.168.1.101
Oct  2 08:55:45 dnsmasq[454]: query[PTR] 3.1.168.192.in-addr.arpa from 192.168.1.101
Oct  2 08:55:45 dnsmasq[454]: query[PTR] 4.1.168.192.in-addr.arpa from 192.168.1.101
..
Oct  2 08:55:45 dnsmasq[454]: query[PTR] 251.1.168.192.in-addr.arpa from 192.168.1.101
Oct  2 08:55:45 dnsmasq[454]: query[PTR] 252.1.168.192.in-addr.arpa from 192.168.1.101
Oct  2 08:55:45 dnsmasq[454]: query[PTR] 253.1.168.192.in-addr.arpa from 192.168.1.101
Oct  2 08:55:45 dnsmasq[454]: query[PTR] 254.1.168.192.in-addr.arpa from 192.168.1.101

[jpgpi250]

read here (REFRESH_HOSTNAMES=IPV4|ALL|UNKNOWN|NONE).

[csh]

A stated in the above post I already did that.
This option does not work for me:

REFRESH_HOSTNAMES=NONE - Don't do any hourly PTR lookups This means we look host names up exactly once (when we first see a client) and never again. You may miss future changes of host names.