If your blog is monetized with third-party providers or you’ve manually integrated AdSense in your blog, you will need to manually set up the content of the ads.txt file.
Sign in to Blogger.
In the top left, click the Down arrow .
Click the blog you want to set up an ads.txt file on.
On the left, click Settings.
Under "Settings," click Search preferences.
Under "Monetization," find "Custom ads.txt" and click Edit.
Click Yes.
Copy the settings from your third-party monetization provider and paste them in the text box.
Click Save settings.
Optional: To check the content of your ads.txt file, go to http://
