Open https://yourdomain.com/ads.txt and confirm it returns plain text. Use the publisher record copied from your own AdSense account. If other ad networks are authorized to sell inventory, keep their valid records; do not replace the whole file with one sample line. Google’s ads.txt guide explains formatting, placement, and status checks.
Check both apex and www behavior if your site redirects between them. The file should be available at the location AdSense checks for the submitted domain. After an edit, revisit the file and use the account’s “check for updates” option if offered; Google notes that status changes can take time.
Use SiteReadyScore to check public file reachability, then verify every seller entry against the relevant account or ad network documentation. A scanner cannot confirm authorization or publisher identity.