How to show real source ip address after iptables dnat forward?

[Miroxyz]

Gateway
ip: 192.168.1.1

AdguardHome
ip: 192.168.1.2

My PC
ip: 192.168.1.3
gateway: 192.168.1.1
dns: 192.168.1.1

I add a iptables rule in my gateway to forward dns request to AdguardHome.
iptables -t nat -A PREROUTING -i eth1 -p udp --dport 53 -j DNAT --to 192.168.1.2

In AdguardHome query log, I got the gateway ip address. How can I get the real source ip address？