The problem is Chrome. After the introduction of ver 84 and up the Async DNS option is no longer in chrome://flags. You need to uninstall Chrome updates in you apps settings and install the last version 83 from a site like UptoDown. This brought back the Async DNS option and fixed the issue with ads coming through Chrome. Async DNS must be set to DISABLED.
Down side? Chrome can’t be updated till Google reintroduces the Async DNS option on later Chrome versions.
Link to old Chrome version apk here…
https://chrome.en.uptodown.com/android/download/2268249
Hope this solves everyone’s problem! I have Blokada 4.11 and working fine with Chrome version 83.0.4103.106. Android 10, Samsung Galaxy A50.