forum search with: “Failed to return clean data” sort by Latest Post.
https://forum.qubes-os.org/search?q=Failed%20to%20return%20clean%20data%20order%3Alatest
in first results: (github related issue in the first below link)
https://forum.qubes-os.org/t/debian-11-template-fails-to-upgrade/20565/4