thanks

You may need to log into your adsense account and click on My ads - Create ads depending on the size you want. I think you can only display three ads in sites that are not . (not too sure now)...
Anyway create the ads, load the ad codes, copy the ad codes and

Go over to your website dashboard and place the ads where you want it. If you are using wordpress, you can download the Quick Adsense plugin, it helps in placing ads where you want them by pasting the ad codes where you want each one to appear on your site. There are still other plugins for adsense...that's the one I use.
If you would like one on your sidebar, then go to appearance-widgets and drop the Quick adsense widget where you want on the sidebar.
Hope it helps.

if you have done everything possible and ad still not showing, do report to google. their contact email is in confirmation letter in your email inbox

what type of adsense are you using is it HOSTED or NON-HOSTED account

great664:
I was using www.example..com and adsense was showing well on it, i decided to buy a domain name so as to remove the ., after doing everything and it has redirected my adsense stop display. how can i make it to display again on naijatrumpet.com

if your adsense is non hosted, then go to your adsense dashboard and scroll to settings. Site management. There you will see list of site that is added to the authorized site to display adsense. If the new domain is not there, then add it. Probably you ticked the box to only allow adsense display on site which you authorized