You'll need to provide a bit more information if you want assistance from the Community Forum.
In what way is it not working?
What happens when you configure it?
Is your mobile data working ok apart from this?
Do you have an iPhone by any chance?
If so then you'll probably need to look at this article - in particular the section titled "A note about personal hotspot setup on iPhones":
If you need to contact 48 support about this then see the links in my signature below.
