User notifications for an event not working

[JammyDodger]

It should appear in their notification menu like so:

But I think I can replicate this:

• Create an event
• Use ‘Notify user’ option and select a user
• User does not receive a notification

However -

• Create an event
• Use ‘Notify user’ option and select a group
• Members of the group receive a notification as expected

Something doesn’t seem to be firing for the individual users.