WPBakery elements not showing properly

I have 2 website, both on the same Admin network
After I installed Unicon theme on admin site, i realized that one site have significantly less WPBakery elements than the other.

Here’s the screenshot on the 2 sites, both are showing WPBakery’s Content tab
1st web: https://imgur.com/a/KRGWRqP
2nd web: https://imgur.com/a/ClhsDk9

Settings on both sites are mostly identical.
I imported Unicon demo on the 1st web, built a Home page there, then exported the page’s data to the other.
Since the 2nd web didn’t have all demo data imported, I’m thinking that might be the problem? But then I am unable to finish the data import on the 2nd web, the loading icon keeps spinning forever.

I would like to know what is going wrong and if I could fix it? Thank you

Ticket