Is AdMob dying or trying to kill us?

[Windows Central Question]

I have a big trouble with AdMob these days, the fill rate dropped 90% in 2 days. On May 6, my fill rate was 99%, on next day was 40% and on May 8 was 10% and not increased anymore. I found on Internet, other devs with same issue. Everyone starting on May 7.
The contract of Google with advertisers was terminated? That's normal? Somebody know?
Is it a located problem or is happening with all WP devs?
By now I'm using pubCenter (AdMediator), not is good enough, but is better than AdMob.