After yesterday Google introduced the Search Console Beta version , now Google added Ads.txt on Blogger . 
How to Enable Ads.txt on Blogger

What is Ads.txt?

Ads.txt is an initiative of the Interactive Advertising Bureau Tech Lab (IAB) to promote and improve transparency in program advertising. This is an easy way for Adsense publishers to clearly point out to authorized buyers to sell their inventory. 

Actually for Blogger Ads.txt already existed but now you can edit Ads.txt as you wish and for you who get this warning message like this
Your earnings are at risk - One or more of your ads.txt files does not contain the AdSense publisher ID. Fix this issue right now to avoid having a serious impact on your revenue.

On the Google Adsense dashboard, Google suggests you to enable Ads.txt on your blog. 

How to Enable Ads.txt on Blogger?

To enable Ads.txt on Blogger, you can set it in Blogger Dashboard > Settings > Search preferences > Monetize > custom ads.txt > Then click edit choose Yes and fill in the following code in the ads.txt column 

Cara Mengaktifkan Ads.txt di Blogger, pub-0000000000000000, DIRECT, f08c47fec0942fa0 

Replace pub-0000000000000000 with your Adsense ID buddy then click Save changes . 

Adsense IDs can be found in your Google Adsense dashboard like the example below 

Cara Mengaktifkan Ads.txt di Blogger

To check whether Ads.txt is enabled, you can check in the browser search tab with a link like this 

Rename_domain with your blog address. 

For those of you who have blogs with sub domains of the primary domain, you do not need to enable this Ads.txt. Just enough on blogs with the primary domain only enabled

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Source: Arlinadzgn