AVD Session Hosts in Azure, have done all the relevant registry settings and UEFICA2023Status is in progress. WindowsUEFICA2023Capable is 2.

UEFICA2023Error = 0x80070005 (Access Denied)

Does not complete fully, AvailableUpdates is 4004, states KEKLastUpdateErrorReason:Firmware_Unknown. It is doing this for quite a few clients. Is there further steps to follow?  ConfidenceLevel is still Under Observation. We have set ManagedOptIn to 1. Been set for the last couple of months.