Problems with locking the screen (and gnome-shell then crashing) lately have mostly been bug 1877774, which you don't seem to have the fix for... To get the fix please try:
sudo apt update
sudo apt full-upgrade
Reboot
and then verify your gnome-shell package is at least version 3.36.3.
Problems with locking the screen (and gnome-shell then crashing) lately have mostly been bug 1877774, which you don't seem to have the fix for... To get the fix please try:
sudo apt update
sudo apt full-upgrade
Reboot
and then verify your gnome-shell package is at least version 3.36.3.