Dns not working when one of dual-wan is down

[umtsti]

Hello, I have pfsense with two WANs, both configured with static IP on each router. Those two WAN exist in gateway group with Tier1 and Tier2. Right now tier1 is down so the second one is up as set as default gateway on dashboard. That wan group selected as default gateway.

I have two DNS server set on "General Setup" with "none" gateway selection, both seems to be working on "Status -> DNS resolver section". Im using DNS resolver with following settings;

My problem is, when tier1 WAN is down, DNS queries on clients doest work. But when I check, pfsense itself can make successfull dns queries without problem.

[umtsti]

My problem is, when tier1 WAN is down, when all interfaces which are set "Default" as gateway has no internet connection. If I set that value the one "Tier 2" internet connection works how its supposed to be.