Something is wrong with Masteries

Ever since the new client, there have been instances where masteries in Champ Select go crazy. They get sort of glitch out, not letting me change the masteries within a page, or even being able to change a page for different champs, etc. Sometimes it even glitches WHILE I'm changing masteries. Just now I was trying to change my masteries for Jarvan , taking some points out of Ferocity to move to Resolve, when it just froze. I couldn't remove or add new points to the tree, or even change the page. This has happened about 3 times now, once even going into a game without a Keystone due to this freeze mid-mastery change. If someone could explain the problem, or a Rioter to be alerted about it, I'd be happy
Report as:
Offensive Spam Harassment Incorrect Board