Champion select BUG

I was going to play yasuo and i was 4th pick, so i asked my mid laner (first pick) to pick me Yasuo for me. After he picked me Yasuo and it was my turn to pick, I typed in xerath and was about to click on Xerath but then he just disappeared and then i untype xerath from my search bar and i didnt have even half of the champions i own in the champion select... wth? i lost 3lp and 6min because of this zzz.