I tried autocompleting a druid deck for this week’s tavern brawl then tried deleting it. It brought me to the “pick a class” screen again and after i picked druid again, my druid deck was still listed. (Like how in my collection you can save multiple decks; it had my first druid decklist still saved and was trying to create another decklist).
Trying to delete the old decklist froze the game and I haven’t been able to enter the Tavern brawl ever since.