site content change , but google ads not change complete .why?

[heelz]

hello :
I am new to here :
I have a site some days ago , I got approved by googleadsense .
and yesterday , I change my site content . but in my site ,some pages (ablut 20%) of my new site display the ads NOT relate to my new content , but relate my old content ,
but in my new site , there are not any keywords of my old content ,
why this will happen?how can I change it?
anyone can help me?

[annej]

The AdSense spider may not have checked you since you changed everything. Until that happens Google will set ads based on what the old pages had on them.

[MikeNoLastName]

We've had that experience too. Many times it's simply as the last person said about the crawler. You can do an adsense preview tool check which seems to force a quicker spidering. But if it doesn't change in 48 hours, my theory is that it happens when you get enough of a history with the old ads "WORKING" really well that the algorithm is hesitant to experiment and mess with it and change them from "winners". In that case you should notice a very gradual trend towards phasing in new keywords one or two at a time until people start clicking on them more than the old ones. It could easily take a week or two.