You have re-imaged your ESXI hosts that were participating in a vSAN cluster.
Vmware vSAN
ESXI hosts re-imaged due to loss of root password
There are two ways to get the re-imaged hosts to participate in the vSAN cluster:
If the vCenter is available or able to be restored from backup: How to add a host back to a vSAN cluster after an ESXi host rebuild
If the vCenter is unavailable or unable to be restored from backup: a new vCenter will need to be deployed and then you can migrate the vsan