Block of subnetwork that aint in my network

[process]

Im woundering why it is so that I see this block on my IoT 192.168.20.x vlan when source is 224.0.0.251:5353 (seems to be a multicast address) and destination is 192.168.72.251:5353 (or 192.168.72.180, 192.168.72.176, 192.168.72.8 ).
I havn't any 192.168.72.x vlan in my network so why is it heading for that sub network?

Before I got my opnsense solution I had another router (without vlands) that were running on 192.168.72.1 by default.
The only thing that I previously had a static ip on the unit was my shelly devices. But all of them are moved to 192.168.20.1. Could there be some old settings that is still in use? Will opnsense present the static ip on the unit even if it has in practice a 192.168.20.x ip? I can't see any 192.168.72.x ips in dhcp leases .

Interface	Source	Destination	Proto	Label
IoT20	192.168.72.251:5353	224.0.0.251:5353	udp	Default deny / state violation rulel