Problems with connection with Stubby and Quad9 on Linux Mint 21.1

[D4vRAM369]

Hi, I have some problems with Stubby with Quad9 configured as DNS. The configuration file of it is ok, with Quad9 not commented #.
I use Linux Mint 21.1, and I have 2 connections network profiles: one of them is configured with 9.9.9.9 of Quad9, also in router configuration, and the another one with 127.0.0.1 as is indicated for the use of Stubby. I rather have 2 in case of problem with this last one. When I enter on profile 2 (127.0.0.1) and Stubby enabled since PC is turning on, the webs doesn't loads, give me DNS error or don't finish of show the web. I need to switch to profile1, the first mentioned profile, and everything is ok, and later to profile2, and then works the navigation.

Until here everything is ok, that isn't a problem at all, a bit annoying, but really managable. But in other hand, since a time ago I have problems with the network profile needed to the proper work of Stubby (127.0.0.1) to listen Spotify: it doesn't load the songs or not shows up anything. I switch to profile1 and works great since that moment, but I switch again to profile2 and only the song I listening could be played, the another ones can't, isn't working Spotify with the needed network profile with the local IP following the correct method to use Stubby. I also have the same problem with Nuclear, didn't reproduce anything neither with profile2.

Hope this could be solved because is a problem. Some people recommended me NextDNS for Linux, but I would rather keep using Stubby. A GUI would be great, but not matter. But this... This is a problem, I can't use Stubby without 127.0.0.1 like configurated IP, and of that way Spotify and Nuclear don't works.

Regards.