Slim auto-login disallow me to login with another user

[znavko]

Hello, Guix! I have configured Slim to do autologin with user 'mom'. I use 
xfce4+slim. So it works.
But I have expected it is possible to logout from 'mom' and login with 'bob'.
But not! After pressing in Xfce4 'Logout' it does logout but thereafter login 
again with mom.
Please, is it possible to do something?
I tried to use another tty to kill slim, xorg services but I do not know 
exactly which process to kill and what to run to start session.

My config's lines:
 (users (cons* (user-account (name "bob") (group "users")
 (supplementary-groups '("wheel" "netdev" "audio" "video"))
 (home-directory "/home/bob"))
 (user-account (name "mom") (group "users")
 (supplementary-groups '("wheel" "netdev" "audio" "video"))
 (home-directory "/home/mom"))
 %base-user-accounts))
 (services (cons*
 (service xfce-desktop-service-type)
 (service dhcp-client-service-type)
 (service slim-service-type
 (slim-configuration
 ;;(auto-login? #t)
 ;;(default-user "mom")
 (xorg-configuration
 (xorg-configuration
 (extra-config 
 '("Section "InputClass"
Identifier "touchpad"
Driver "libinput"
MatchIsTouchpad "on"
Option "Tapping" "on"
EndSection")
 ))))
 )

 (modify-services 
 (remove (lambda (service)
 (member (service-kind service)
 (list ntp-service-type avahi-service-type
 bluetooth-service network-manager-service-type
 gdm-service-type)))
 %desktop-services) ;end of remove lambda services

 (wpa-supplicant-service-type config =>
 (wpa-supplicant-configuration
 (interface "wlp2s0")
 (config-file "/etc/wpa_supplicant/wpa_supplicant.conf")))

 (elogind-service-type
 c => (elogind-configuration (handle-lid-switch 'ignore)))
 ) ;;end of modify-services
 )) ;;end of services

 ;; Allow resolution of '.local' host names with mDNS.
 (name-service-switch %mdns-host-lookup-nss)

 ;;blacklist ugly sound speaker, blacklist ideapad_laptop for prevent soft 
blocking wlan
 (kernel-arguments 
'("modprobe.blacklist=pcspkr,snd_pcsp,bluetooth,ideapad_laptop"))