DNS setting isn't persistent on Neon

I'm quite a privacy nut. I've done everything I can to be as anonymous as I can be on the Internet. I use a VPN and thought I changed my DNS search settings. However, after checking it, I see it's returned to AT&T. I use them as my provider and they provide me with a router that doubles as a DHCP server. I've gone into Network Manager and changed the DNS for IPV4 and IPV6 to manual and point to 1.0.0.1 and 1.1.1.1, click apply and close. Then when I reopen Network Manager, it's set back to Automatic. I can edit /etc/resolv.conf with the info and for that session 1.0.0.1 will be my DNS server. But when I reboot, it's back to AT&T. Besides setting up my own DHCP server, how can I get persistent control of my DNS Search server?

I'm running KDE Neon 5.22 (Ubuntu based OS).