Unable to create multiple VNF instances of same VDU from vnfd yaml file

I have created one vnfd yaml file where I have defined one VDU. In the same yaml file, I have also defined a policy as mentioned in https://docs.openstack.org/tacker/latest/user/scale_usage_guide.html

When I try to create the instance using (openstack vnf create) - it failed with "heat-translator failed: - [Errno 13] Permission denied: 'SP1_res.yaml' "

I am using openstack version 3.16.1 and tacker version 0.14.0. Looks similar to https://answers.launchpad.net/tacker/+question/659219 - which is resolved

Is this the only way to create multiple instances of same VDU. I dont want to define 10 VDUs in the yaml file - instead is there any property to specify the count - how many VNF instances to create from this VDU?