I’m also running the latest version of this plugin and the notification is always shown. I tried dismissing via the close button at the top right, but it keeps re-showing upon refresh. I tried going to Preview Neve to actually do what it suggests, but it keeps re-showing upon refresh. I tried actually installing the Neve theme (obviously not activating since I have a different theme being used on my site), but it keeps re-showing.
It appears nothing shy of actually using that theme will have this message go away (I’m assuming that would get it to go away, but I don’t want to use that theme so I haven’t confirmed.)
I have tested multiple sites and this same problematic behavior is consistent across all of them (also coinciding with everyone else here & in other support forum topics [see https://www.ads-software.com/support/topic/any-way-to-hide-theme-preview-message-forever/ ] having this happening as well.)