Champion Reset Exp?

I was wondering if there's a way to reset your champion skill exp? I was playing with a guy earlier and it says he only has level 1 champions even though he's diamond... How is this possible?

The guys name is "Kaptain Kek" in NA. He has over 600 wins on Summoner's Rift and like no champion exp even though on Lolking it says he has been playing since Season 3 with multiple champions. Another thing I want to address is his badges too such as the teamwork badge he has like no likes.