A few observations from your debug log.
You have multiple IP's assigned to the same interface on the Pi. This can cause problems if you did not set this up intentionally.
*** [ DIAGNOSING ]: Networking
[✓] IPv4 address(es) bound to the eth0 interface:
10.0.0.123/24 does not match the IP found in /etc/pihole/setupVars.conf (https://discourse.pi-hole.net/t/use-ipv6-ula-addresses-for-pi-hole/2127)
10.0.0.3/24 matches the IP found in /etc/pihole/setupVars.conf
You have multiple gateways assigned.
[i] Default IPv4 gateway: 10.0.0.2
10.0.0.2
10.0.3.2
- Pinging 10.0.0.2
10.0.0.2
10.0.3.2...
[✗] Gateway did not respond. (Why is a default gateway important for Pi-hole?)
Here is another indication that your blocklists contain some garbage:
*** [ DIAGNOSING ]: Name resolution (IPv4) using a random blocked domain and a known ad-serving domain
[✗] Failed to resolve r9---sn--gqn-vu2l.googlevideo.com via localhost (127.0.0.1)
[✗] Failed to resolve r9---sn--gqn-vu2l.googlevideo.com via Pi-hole (10.0.0.3)
[✓] doubleclick.com is 172.217.16.110 via a remote, public DNS server (8.8.8.8)
dig +short r9---sn--gqn-vu2l.googlevideo.com
dig: 'r9---sn--gqn-vu2l.googlevideo.com' is not a legal IDN name (string contains forbidden two hyphens pattern), use +noidnin