My Pi-hole is accessible via WLAN (wlan0). It is located on the RasPi Zero 2 W. Pi-hole is my DHCP server, on the router DHCP is disabled. As DNS I use Unbound without additional DoT resolvers. IPv6 in the router and on Pi-hole disabled. Works actually also without problems, all my devices get their IP (all static) from the Pi-Hole, go to the internet and ads are blocked.
If I am not at home for a longer time, I always deactivated my WLAN in the router. Then logically the Pi-hole is no longer accessible.
When I reactivate the WLAN in the router after it was deactivated, I can no longer reach the Pi-hole via the browser. The devices can't access the Internet and the PC has no IP4 connectivity and no network access.
Then I always have to go the detour via the router, activate DHCP on it and provide a public DNS (188.8.131.52) until the devices automatically get network access again, after the lease time.
Then I can access the Pi-hole, disable DHCP there briefly, wait a minute, then re-enable and on the router disable DHCP regularly and change DNS back to Pi-hole IP.
Then everything works again until I deactivate the WLAN again and activate it later. Then the same problems start again and I have to go the detour via the router DHCP...
I always get this error message in the Pi-hole:
no address range available for DHCP request via wlan0