No key fragments in 3 weeks? (13 June/16)

So the last week of May I got no key fragments, which I find reasonable since the chances of getting a key drop lower as you earn more keys. This probability plot/graph however is refreshed every month, which means you have the highest chances in the start of every month, and it has been 2 weeks since the start of June and still no keys. I know friends that experience same problem. Anyone else here? p.s. i play alot