EDIT: Also, despite being logged in to the Yahoo Fantasy app this league doesn't show up and the dynasty one doesn't either, what's the deal? I can still do everything through a web browser just fine but it's weird.
Make sure you don't have them hidden. You'll have to click on the page that shows all the leagues. Then then menu button. Then see if they are down at the bottom hidden. If they are, you'll have to click "show" and then they'll show up. You can organize the order of your leagues from that page too. I hide all the yahoo daily fantasy shit normall.