Masteries Bug Report in Champion Select.

As far as you read the title, the problem I am having is first I was checking out my friends masteries page. When I started an game up.. I had his masteries to select from. Not much later I was hitting one of them then it says "These Masteries page cannot be found" weird is it not? Now I guess it is fixed but maybe this is a common bug not sure though.. I got an Image of it but as I can see I am not able to upload it here?

Greetz.. Nat von Sweet