1. I changed the cluster name of vCenter Host Cluster.
2. Then requested the VM from Self Service Portal
3. Request is failed with this message "Request failed: Machine Ranjna001: CloneVM : Object reference not set to an instance of an object.."
4. Then i connected with Self Service Portal as infra admin role user to check the log message generated by this issue and this is error message that was available in the logs "DC: c7668cde-36d2-4669-9086-4b459078e3d7: inventory: vSphereAgent: Cluster01: Received failed data collection response, StatusID = 11848de2-a374-4930-a664-182bb69df8d9 : Object reference not set to an instance of an object."
Rename your cluster name to old name to provision the machine without failure. And no need to trigger the data collection.