If you have entered a "working key" but YogaDNS shows errors, here is what is likely happening:
One interesting paper related to DNS and privacy is: yogadns license key work
Some license keys found on forums or GitHub repositories will appear to work. You paste the key, YogaDNS accepts it, and the "Unlicensed" watermark disappears. For a few hours—or days—you feel victorious. If you have entered a "working key" but
: The free version of YogaDNS remains fully functional for standard usage, including capturing DNS requests at the system level and routing them via modern protocols like DoH (DNS over HTTPS), DNSCrypt, and DNS over QUIC. : The free version of YogaDNS remains fully
: After the trial, you must enter a purchased license key to keep Pro features. A Single Pro License costs $39.95 and is a lifetime license for minor version updates.