Confused about settings, who do i pay for help ?

Hi,

I am just doing IPv4 linked on my router and setting up Firefox on my Windows 10 desktop.

On my settings page it says my DNS servers are: 

45.90.28.171  
45.90.30.171  

and that I am linked √

When i ping these i get 36ms for 45.90.30.171 and 96ms for the other.

Why such a difference ? Should i still be using the slower one ?

Before i subscribed i was just looking for some server ip's to put in my router like i have always done. and i came across 45.90.28.166 And 45.90.30.166
The 45.90.30.166 pings at 32ms and the other at 80ms. Again a pair with a big differential in ping response.

So these are faster than the ones my setup page says to use. Not by much i guess but i can notice a difference.

Does my router have to have the exact ones on my setup page for Nextdns to function correctly ? why?
or....
Can i use the 2 fastest ones ? ; 45.90.30.166 and
45.90.30.171  or will my NextDNS profile/settings not work ?

Also, I was working on tweaks with DeepSeek on Firefox and it said to use 45.90.28.0 or 45.90.30.0
for my "network.trr.bootstrapAddress" but not to use the same ones on my router.  Is this correct? I have the custom url from my Next setup page in my Firefox DNS over HTTPS  settings.

I hope i can get some help. I thought i would when i paid the subscription but that aint happening.

thanks.