Logrotate: wtmp:3 unknown user ‘prime’ Ubuntu 20.04

Lorotate gives error:

Oct 31 00:00:01 foo logrotate[364456]: error: wtmp:3 unknown user 'prime'
Oct 31 00:00:01 foo logrotate[364456]: error: found error in /var/log/wtmp , skipping

I have in /etc/logrotate.d/wtmp

/var/log/wtmp {
    su prime gadmin
    missingok
    monthly
    create 0664 root utmp
    minsize 1M
    rotate 1
}

Ownership:

-rw-rw-r--  1 root    utmp             160128 Oct 30 23:10 wtmp

There is no user prime in passwd.

What can be set in logrotate wtmp?