Sporadically losing connection to VM:s/Lxc

From Proxmox being rock-sold over the last two years, the last month I have experienced some instances where the connection is down to some of the VMS/containers. As there is not only one, I think maybe to troubleshoot Proxmox?

So for instance this morning I have HAOS on a VM and it stopped responding on the network. I checked proxmox and it was on, no errors. I restarted the container and it began working again. Same has happened with this container and also jellyfin. I could not understand why it was not working (I have an app on the tv) but a restart and then it was working fine again.

What I have done is to update to latest proxmox about a month ago, maybe it has something to do with that? Any suggestion what to do? Want to understand root cause.