In case you are using Google Ads, please make sure you add the Google ID to yourdomain.com/ads.txt file.
To add the Google ID, just copy-paste the following line to the ads.txt file (please, replace 0000000000000000 with your Google ID):
google.com, pub-0000000000000000, DIRECT, f08c47fec0942fa0
You can read more about ads.txt, and find details on how to implement it below: