Adsense ads pasted but some are not showing up..

You may paste upto three ad units,up to three link units,three referral units,maximum of two Google AdSense for search boxes,,ANDthree referral units in addition to the ad units,search boxes,on each page.Any more numbers than that specified will give you a blank space.SO ASSUMING YOU HAVE NOT EXCEEDED THE SPECIFIED NUMBER OF ADS DO THIS>>>Take time and check for open tags or incomplete pasting of the adcodes..ALTERNATIVELY copy the adsense codes from your adsense account once again and paste it taking care to ensure that every single line of code has been copied and pasted.If it is still not showing up,visit your site with a different browser.