Notifications settings missing

Hello,

M365 Business Standard, global admin

I've created a couple of  plans in Planner for a couple of users, however we don't receive any notification when a new task is created or completed.

Let's say I create a task - I assign this task to another user - the users completes the task - I don't get any notification. How come? It's like basic functionality, so I assume there must be something wrong with the set up. 

In the web I found a couple of screenshots of the setttings but they are not available in my view:
 

My view:

What am I missing ? Is it possible to check/change the setting via powershell ?