iOS profile not working when NextDNS setup on home router

Here the issue that I can't understand completely.

I have nextdns configured at the router (Asus) using ddns (Profile 1). I have also a couple of "personal" profiles for me (Profile 2) and my partner (profile 3).  I have also profile 4 that is for testing and it allows every traffic.
The profiles 2 and 3 are: for my iphone and tailscale (PC and Nas) (profile 2) while profile 3 on an iphone only. The issues are similar on profiles 2 and 3 on iOS devices. Tailscale via profile 2 is not effected.

What happens, by using the apple configuration profile is the following:

- profile 2 or 3 enable & wifi connected: nextdns can't resolve anything and internet is absent

- profile 2 or 3 enable & wifi off (5g only): nextdns profile 2 or 3 resolves any request - all fine

- profile 2 or 3 disable & wifi connected: nextdns profile 1 is the one resolving and everything is fine

- profile 4 enable % wifi connected: nextdns can't resolve anything and internet is absent

I am no expert but looks like a issue with the apple configuration profile but I can't really understanding more than this and get to root. I need help