If you're using an advert banner service such as Google Adsense, they will most likely ask you to setup something called "ads.txt".
We'll not go into the details of what ads.txt is, there are many guides available for that. Here we will show how to create an ads.txt file using either WordPress or Blogger/Blogspot.
The easiest way to create the ads.txt file on your WordPress site is to use the Ads.txt Manager plugin.
You can access the ads.txt settings in Blogger/Blogspot by going to Settings > Search preferences in your blog's dashboard. This allows you to copy and paste the required information into your blog's ads.txt file.