Store selection changes when it refreshes

So I had 980 RP and I wanted to buy 2 mystery skins. I bought one didn't get exactly what I wanted so I was like okay I'll buy a second. I go to buy it and the store refreshes right before I click on the mystery skin so that it moves to the bloody champion section of the store! I then proceed to buy a mystery champion on accident because when it refreshes it changes section. Honestly this is soooo bull because I have every champion I want and I got Corki man. I'm not asking for a refund because I know Riot is too cheap to do that but all I'm asking is for the client to not change the section you're looking at when it refreshes.