Why did majority of my decks got banned?

Envoy300

Majority of my decks I obtained using codes and some were given freely but now the game is saying I don’t own the cards and expects me to re purchase them even after they were included in some Pokémon decks I bought and added with codes!!! What a rip off!!

TechHog

You're mistaken. Every year something called a rotation happens. That results in the oldest cards in standard by year no longer being legal. You still have the cards, but they can no longer be used in standard. Cards with a D in the lower-left corner are no longer legal.