Dig Command Not Working MacOS Mojave

I figured it out. It appears to be Xfinity/Comcast. When you both said it was working for you, that gave me the idea that it might not be Mojave. I run dig all of the time, but maybe not in the last month. I turned on the hotspot on my iphone and connected the Mac to it. The dig command worked without using "+tcp". It appears that Xfinity/Comcast are blocking outbound UDP on port 53.

Thanks for your help. I really appreciate it.

That's the correct command.

I just bought an iMac in December and it's running Mojave. It has the same problem.

dig @ns1.google.com www.google.com Does not work

dig + tcp @ns1.google.com www.google.com Works

host and nslookup both work.

When I examined the packets with tcpdump, I could see the UDP packets going out, but nothing coming back. When I did the same for nslookup, I could see packets coming back. This is weird.

The firewall is enabled on the Mac. I turned it off and still had the same problem. The was firewall was enabled on Sierra too, and I didn't make any changes when I upgraded to Mojave.