After migration from 1.2 → 2.0 almost everything work fine, but some user who got a correct “first_name” “last_name” become “UNKNOWN” “last_name”.
It’s not a big deal but is they are anyway to fix that ? I got the correct information in LDAP (for example).
Most likely they had both names in the first/last name field, and an empty last/first name. There’s no good way to determine what should go where in such a case…
Since you said just a few users are affected it’s probably best if you just fix them manually in the admin area.