[ubuntu] Error kvm connection with libvirt

Hello,

I use Ubuntu 19.10 and I try to use a VM with qemu/KVM with virt-manager.

I created my bridge and installed a VM with success, but since the reboot of my conputer, I lost the network. I can communicate between my VMs, but I can't access to Internet from them.

I tried to reinstall the connection, but I have always the same error.

Help me please...

thanks by advance
++
Laurent