I have the plugin to put a code after every first post in a thread, I used adsense and put the code in. Why do 3 adsense ads pop up right on top of each other rather than just 1?
Probably because you have the variable 3 times in the template, remove two of the duplicates.
I can't edit the template, it doesn't appear in the templates.
What do you mean by 'it doesn't appear'...?? There will be some template changes made to make the ads show in the threads...