DNS Doesn't work on 24.7.11 when plugging in Openwrt router

[machine3531]

Versions
OPNsense 24.7.11_2-amd64
FreeBSD 14.1-RELEASE-p6
OpenSSL 3.0.15
OpenWRT 23.05 on Banana Pi R3

Hello everyone. I want to use OpenWRT as my Wireless Access Point, but DNS works for the router itself when I ping cloudflare from Luci, but all connected devices don't have DNS working. I manually set my DNS server on my Debian 12 laptop to 1.1.1.1 and DNS still doesn't work I can ping 1.1.1.1, but not cloudflare.com. If I unplug the Banana Pi and plug it into my ISP router, DNS works just fine. What is wrong?

[cookiemonster]

Impossible to tell with what you have instead of how you have them configured/setup to interact with each other in terms of networking ;)

[machine3531]

That is a good point. I did a fresh install of OPNsense and a fresh install of Openwrt. I don't know  what settings could cause this issue. Do you have any ideas? I clearly don't know a much.

[EricPerl]

Still insufficient... You might want to keep it simple.

It's not clear whether you're keeping your ISP router when testing with OPN.
Option 1: Internet <-> ISP Router <-> OPN <-> AP? or
Option 2: Internet <-> [optional: ISP device in bridge mode <->] OPN <-> AP?

With option 1, you have to make sure the LAN side of both routers (ISP & OPN) don't have overlapping IP ranges.
Use of DHCP on the routers helps making sure you get IP in the proper range, and typically sets DNS to point to the LAN gateway.

Then you test IP connectivity (IP in expected range, ping gateway, ping public DNS, DNS resolution via nslookup or dig) from the edge towards the inside of your network:
On the ISP router itself, machine connected to ISP router, OPN itself (Interfaces > Diagnostics), machine connected to OPN, AP, machine connected to AP.