Bridged Network - connection between macOS host and macOS guest is lost after 1-2 mins

**Configuration**
* UTM Version: 4.6.4
* macOS Version: Sequioa 15.4
* Mac Chip: M3

I have an Apple Mac M3 host with macOS Sequioa 15.4 and UTM running with a guest also with macOS Sequioa 15.4.
When I restart the VM, everything is fine.
I can access the guest from the host and vice versa.
I can also access the guest from an external Mac in the network.

But after a random time, suddenly no connection is possible between host and guest and vice versa.
The strange thing is that the external Mac can always access the guest.

If I press ‘Renew DHCP lease’ in macOS guest or deactivate and activate Ethernet, the connection between host and guest works again for a short time of maybe 1-2 minutes before it drops again.
Sometimes the connection remains active a little longer after restarting the VM.
I have no idea what the problem is and it is very annoying that I have to restart my guest network dozens of times a day.
Does anyone here have a solution?