Screen blanking not always working while on login screen

### What Happened?

When logged out the screen stays on.
Same problem while logged in.

### Steps to Reproduce

Using ElementaryOS on all-in-one PC (ADJ) with three user accounts as family PC.
When switching between different accounts and leaving the computer on, it should blank te screen.
Sometimes happens, sometimes not...

### Expected Behavior

Correct screen blanking behavior.

### OS Version

6.x (Odin)

### Software Version

Latest release (I have run all updates)

### Log Output

```shell
Which log to check for this functionality?
```

### Hardware Info