How interesting, there is a, new to me, Security Feature for the Admin Home user (Encryption Lock). Does This account have to be pin? yes if you want the “Automatically Sign In/off” slider available for the app.
I did test that plus reset cache, restart server, restart iOS device, I have also deleted Library and re-added it. I still get the same message on my app and all media library(s) in server version 1.16.0.1226-1-01

