AB's server actually has three different versions of this site on it. One is for PCs and laptops, one is for tablets and the other is for phones. So, depending upon which type of device you're using, what you see might not exactly match up with what I see.
However, when I first click on 'View your profile', I see a box to activate/deactivate my avatar underneath the statistics:
https://i.postimg.cc/pLTTrZ8S/Profile1.jpg
If I then click on 'Edit my profile', there's a tick beneath my avatar to show that it's activated:
https://i.postimg.cc/65QwfQ32/Profile2.jpg
If your avatar isn't showing up, it's because AB hasn't got the same email address in your registration details as the one that you used to register with Wordpress/Gravatar with.