Daily Play Missions - Select a Champion Bugged

I won my first game of the day and hit level 21 in the same game and it says I completed some Daily Play missions. A screen came up that is supposed to allow me to select 1 of 3 champions (Ekko, Fizz, or Talon) to add to my champion pool, but the screen itself is bugged and doesn't give me the option to select a champion.

I can't get passed this screen unless I select a champion, but there is no option to select a champion, which means I can no longer play League of Legends in any way. I also purchased an EXP boost for so many days, but if this bug isn't fixed immediately then it means my boost and money will be wasted.