YouTube Question Videos getting views and ads running - but RPM is zero?

[Magdelayna]

Can anyone explain why some of my videos have suddenly dropped to zero RPM and so they receive zero revenue?

Before a week ago these videos were doing ok - a few years of similar views,making some revenue - but suddenly its all dropped to zero? Doesnt make sense..

 

[LoFi Rising]

This same thing has happened to me ... my channel (chillhop playlists) has been growing steadily for the past two years plus. In the past few months, my numbers suddenly began dropping, from 1,000-plus to 400 - 500 (yes, tiny channel, but percentage wise a big drop). I don't understand why this should happen when I was steadily growing. Someone said something about YT trying to suppress algorithms.