Some times after an unexpected reboot of nodes or the cluster you will see nodes in node ready state. Also the machine resource in TKG might show as failed
2.X
In order to resolve the issue remove the machine, vspheremachine and vspherevm resources and let the capi/capv recreate these resources
kubectl delete machine MACHINENAME -n NAMESPACE
kubectl delete vspheremachine VSPHEREMACHINENAME -n NAMESPACE
kubectl delete vspherevm VSPHEREVMNAME -n NAMESPACE