marking packet for torrent IP adresses

hy, I need help width mangle and marking packets. I use script to find IP addresses when someone use torrent, and that script work, but just few packet pass through the mangle. I made mangle width this code in terminal:

/ip firewall mangle add chain=prerouting dst-address-list=tracker_dns_ips action=mark-packet new-packet-mark=tracker passthrough=yes

. can anyone tell me where I wrong about this. script take IPs from dns cache