I'm trying to use my AdGuardHome server running on Docker on Ubuntu Server 22.04. For some reason, I cannot assign 192.168.0.200 (my Ubuntu Docker Host IP) to my router at Advanced > Network > Internet > Advanced Settings with "Use the following DNS addresses" selected. The only error message I get is a popup window that says "Invalid Primary DNS Server. Please enter another one." I found a similar thread covering this, but the options they were talking about are not available in the UI for my router.

For reference, DNS over HTTPS and TLS are not configured in AdGuard and I would prefer to not have to go through that trouble as the outward-facing ports from docker are not 443 and 853, since I have Nginx running on the same host.

My only assumption is that TP-Link requires DNS over HTTPS or TLS but there's no documentation that I could find which specifies that. And I know that the AdGuard server is working because I manually set it as my DNS server in Windows on my pc with no issues.

Does anyone have a similar experience to this?