Your debug log shows your custom dhcp configuration to reside at /etc/dnsmasq.d/dnsmasq-wlan0.conf, but you haven't configured Pi-hole to include that directory:
-rw-r--r-- 1 pihole pihole 55K 11 mars 09:50 /etc/pihole/pihole.toml
(…)
[misc]
(…)
etc_dnsmasq_d = false
Please refer to Custom dnsmasq configs not loading.