The user in audit log appears as USER.<UID> instead of user name though the use is defined correctly.
applies to all supported versions on Unix/Linux
The user name is resolved using ladb by default. The user in audit log appears as USER.<UID> if the uid is not registered in ladb.
This can be avoided by registering the uid in ladb using sebuildla command.
# sebuildla -u (or -a)
You can see the registered user in ladb also using sebuildla command.
# sebuildla -U