This issue affects the systems applying the 22.1.1-2p3 and 22.1.2-2p1 patches.
On upgrading to 21.1.1-2p3 or 22.1.2-2p1, the NSX Advanced Load Balancer UI fails to load. The Controller is available and functional via CLI and APIs.
If the patching was done as a separate operation, then we can just rollback the patch
Reference kb: https://avinetworks.com/docs/22.1/flexible-upgrades/#rollback---patch
If the patch operation was done as a part of the upgrade, then we will have to rollback the upgrade.
Reference kb: https://avinetworks.com/docs/22.1/flexible-upgrades/#rollback