I've a new phone (android 11) where ads are not getting blocked. Not sure if it's related but it's the only device on my network with wifi 6, router does support wifi 6 and the phone do indicate it's running wifi 6. I can see the mac and ip address in pihole web, when I'm browsing there is no querys made from the new device.
Actual Behaviour:
Ads would likely to be blocked on my new phone aswell.
My other devices (computer, old phone, watches, tvs are working as normal - ads beeing blocked)
I'm ashamed of myself but I figured it out.. so if someone else is struggling with this aswell.
Somehow my new phone copied a private dns setting from my old phone while restoring a backup. Which led ot the phone did not use the pihole configuration... So simple (: