You have an application hosted on a Compute Engine virtual machine instance that cannot communicate with a resource outside of its subnet. When you review the flow and firewall logs, you do not see any denied traffic listed. During troubleshooting you find: * Flow logs are enabled for the VPC subnet, and all firewall rules are set to log. * The subnetwork logs are not excluded from Stackdriver. * The instance that is hosting the application can communicate outside the subnet. * Other instances within the subnet can communicate outside the subnet. * The external resource initiates communication. What is the most likely cause of the missing log lines?