adsense not showing up often on my php page

my adsense are often absent when i go the php pages , they are sometimes here .
but often not
i cleared cookies but still they do not show up
i used other navigators always same prob

any help

 

Post the page on here so we can help you find the problem if there is any.

Thank You

 

make sure you don't have php session on those pages because bot think it is diffrent page in each session id.

also make sure you didn't place behind login system