Sorry, can’t help, but here just to echo that I too am having the same problem. I first put in the wrong email address. I didn’t get an error then, but obviously couldn’t check the incorrect email to verify. So when I restart the program to put in my correct email address, I get this above 500 error.
Update: it appears it was just a glitch in the Matrix. I was able to register at the /portal/register URL, which allowed me to access the key. Thank you.