Game play is unplayable d/t lag

I am having trouble and wonder if someone can help? I load up Diablo III, click resume game and wait for the loading screen. Once I get into the game it is very laggy, and I’m unable to do anything. I can’t move or select anything in the game. It played fine on this last Friday but on Saturday it was unplayable. Any help will be appreciated. Also I have tried all the trouble shooting methods on the support page and it didn’t help.