When upgrading from 4.7 to 4.8, an ovn-kubernetes cluster containing NetworkPolicies will leave stale ACLs around that will not get deleted, potentially causing connection failures later.
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory (Moderate: OpenShift Container Platform 4.8.2 bug fix and security update), and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHSA-2021:2438