when looking at the friend-list i hovered over my own name and see the "Recent Playstyle" is Kalista, i played her more than 15 games ago and just once, while i have played other champs more than once.
dont know if it is a bug or that it felt like that was the most "important" game to look at.
 Open Firend-list'
 hover over your name at the top
 read the "Recent PlayStyle".