Hi!
I will check with her, she just said she has lots of customers who return because of this issue. I am a bit concerned as it happened to a work friend of mine, but not straight away. There was plenty still left in the tube which she bought mid-year 2014. I went with her to take it back and the SA was really lovely and gave her a new one immediately. It was a RAV. I'll be keeping my receipts from now on from my in store purchases so I guess it will be okay. I'm surprised it would happen with a matte, I expect it more with soft creamy lipsticks.