mDNSResponder using port 53, preventing me from running custom DNS server

So I have been using blocky dns to setup a custom dns server that runs locally on 127.0.0.1 and on port 53. It had been working well for quite some time now and then I decided to update Macos to 15.3.2 and rebooted it and it was no longer working.

sudo lsof -i :53
COMMAND   PID           USER   FD   TYPE             DEVICE SIZE/OFF NODE NAME
mDNSRespo 441 _mdnsresponder   33u  IPv4 0xa70e7309758216e7      0t0  UDP *:domain
mDNSRespo 441 _mdnsresponder   34u  IPv6 0x36f01ded9c565b9f      0t0  UDP *:domain
mDNSRespo 441 _mdnsresponder   35u  IPv4 0x2c23d4c61490f3c1      0t0  TCP *:domain (LISTEN)
mDNSRespo 441 _mdnsresponder   36u  IPv6

and

blocky -c .config/blocky/config.yml
{"level":"error","msg":"server start failed: start udp listener failed: listen udp :53: bind: address already in use","time":"2025-03-12T22:02:10+05:30"}
Error: start udp listener failed: listen udp :53: bind: address already in use

I already have internet sharing disabled and docker isn't running either.