Missing SimCity add-ons in EA App

I purchased the SimCity: Complete Edition on Origin. I've switched to the EA App, as Origin was decommissioned. But the EA App does not recognize that I own all the add-ons. As a result, I cannot claim regions other users have abandoned in which they've used content from the add-ons I'm 'missing.' I've dealt with tech support, who consistently provides incredibly unsatisfactory responses.