I've got the same problem with one of my VM's, after upgrading to 7.1:
Nov 18 13:41:08 pve pvestatd[1139]: VM 117 qmp command failed - VM 117 qmp command 'query-proxmox-support' failed - unable to connect to VM 117 qmp socket - timeout after 31 retries
I tried host CPU and KVM64, but that does...