I'm using the 1-click magento install from digitalocean. I downloaded a theme from templatemonster.com, added the sql database, and unzipped the theme file (fullpackage.zip) to "/app/design/frontend" as directed here. All the permissions are 770 or 775. I ran the magento command "setup:upgrade". My theme is not visible when I go to the themes section of the admin panel. Am I missing a step?
I also tried putting the theme file in several other places like /vendor/magento/.
I'm following these setup instructions from templatemonster.com