Mastery bug

I am having this bug where it says I changed my masteries in the lobby but when I load into a game it still has my old ones. Then every time I try to edit them it goes to my Orianna mastery even though that's not the one I clicked. So ill try to edit something it won't change or I'll be using a different set of masteries. I'm also on the new client. I'm also wondering when I put it in low spec mode why it takes forever for my game to load the end game lobby but it doesn't happen when it's not on.