page views disappear mid-week

Hi, this is the second time my "page views" have disappeared mid-week. On Monday it showed 7 views ( 2 actresses, 2 casting directors etc) on Wednesday this whole Page View heading is gone. A few weeks ago the page views changed the amount of views half way through the week - first it was 4 and then suddenly 3. Wondering what is going on, is there a bug I'm not aware of? Anything I can do to fix this? Thanks!