suddenly dropped

In the past 2 months my views are stable , but since yesterday It drops from that amount to about only 5~6% of my usual views , what is this ? I've check all of my metric data , is youtube ''unrelate'' or ''unsuggested'' my videos ? Not only on 1 of my video , it affects all of my videos ...

Hi guys, Something strange is happening with my most viewed video. I'm concerned about it since this video is responsible for 22% of my earnings. All other videos are fine/normal, there is only issue with one video. This video has around 4.4mil lifetime views and in the past 365 days average...