Not being able to select champion

Hello, there seems to be a bugg on this terrible new laggy client to where i cant select a champion. It shows someone else picking (on enemy team) when its actually my pick. Being that its not my pick i cant select a champion and lock it in. At first it just looked like someone wasnt going to pick then it dodges and turns out its me. I literally have no idea how this is happening but it never happened to me on the legacy client. I truly hope you can fix this issue soon or just give me the ability to use the legacy client so i can play league. (Side Note: I was able to play league on the new client for a little while until this randomly started happening.) PLZ FIX