@waynep16 – I am having the same issue. I have used this plugin before on a couple wordpress sites (4.9/5.1 version of wp) and never had this problem. Built a new site I can upload avatars to profiles but when using the shortcode [avatar] to pages it keeps showing the default avatar. If I change the default avatar it changes and shows the changed avatar as well just not the specific user avatars I uploaded. I cleared cache, removed all extra plugins and no luck.
What weird is I have another plugin which nonporift board management by wired press and it displays the user avatars fine thru its own shortcode. [avatar] just doesnt work.
Did you find a solution to your issue?