It works for me. iPhone X on iOS 13.1.2. Make sure ur phone is on wifi, and it’s plugged in overnight. I think this is the conditions to trigger it to work. U might also want to restart your phone and see if it solve your problem.
Only problem for me is that I’m not getting any notifications / indicator to tell me which apps were updated unless I launch App Store.
I can't remember that last time it worked properly for me, across many iOS devices and versions. I typically just check for updates manually once a day (or less if I don't remember to do so for a few days).