The only weird setting I had the set was the background refresh interval. Mind defaulted off, which seems dumb.

If you don’t set that, it won’t pick up new tasks that you added via the Web UI , and so you might not get notifications for those.

Once I set that I’ve been getting notifications pretty consistently. Also check that you’ve allowed notifications for that app. And the task needs to have a due date set for the notification. Not sure if it also needs a reminder. I think I just do due date.