Clients Fail to Connect to Pi Hole

[bergnt]

Expected Behaviour:

Pi Hole running on RPi 3 (B 1GB) should resolve client DNS requests. Pi Hole admin page should be accessible from client.

Actual Behaviour:

Pi Hole does not resolve DNS request from client. The Pi Hole admin page is only available from the Pi Hole. 192.168.0.135 is Pi Hole

From Client:

nslookup google.com
DNS request timed out.
timeout was 2 seconds.
Server: UnKnown
Address: 192.168.0.135

DNS request timed out.
timeout was 2 seconds.
DNS request timed out.
timeout was 2 seconds.
DNS request timed out.
timeout was 2 seconds.
DNS request timed out.
timeout was 2 seconds.
*** Request to UnKnown timed-out

nslookup google.com 1.1.1.1
Server: one.one.one.one
Address: 1.1.1.1

Non-authoritative answer:
Name: google.com
Addresses: 2607:f8b0:4009:814::200e
142.250.190.142

From RPi
nslookup google.com 192.168.0.135
Server: 192.168.0.135
Address: 192.168.0.135#53

Non-authoritative answer:
Name: google.com
Address: 142.250.191.238
Name: google.com

Debug Token:

https://tricorder.pi-hole.net/Tg7mVDba

[bergnt]

Router is a TP-Link Archer AX3000. I have the RPi set up as DNS server under DHCP options.

My initial thoughts were that my router was blocking port 53 traffic, but disabling the router firewall temporarily did not result in success.