I'm not sure if the github authentication is working. I go to Apply for this job...

I'm not sure if the github authentication is working. I go to Apply for this job, it takes me to github, I click authenticate, then I get this error on on the github_oauth_callback page on remotecoder.io:

{"type":"MongoError","msg":"E11000 duplicate key error index: remotecoder.users.$email_1 dup key: { : null }"}

(My github username is the same as my HN handle)