When making a SOCKS tunnel through the the terminal, sometimes the port might be skipped when you’re in a hurry.
ryan@ryan-laptop:~$ ssh -D email@example.com
Bad dynamic forwarding specification 'firstname.lastname@example.org'
Again, this is probably a silly error. I forgot to specify the port and ssh thought my host connection that server address was the port itself. The fix is easy.
ryan@ryan-laptop:~$ ssh -D 9988 email@example.com
Just add the port and it should work. Missing obvious things is so easy to do when you haven’t had your coffee.