Not sure if this is Profile2 or Field Collection related because both modules are involved. Assuming Profile2 because the Profile table is where the error occurs.

I changed my machine name for a profile from job_seeker to jobseeker. In the Profile table in the DB, it remained job_seeker for a particular user in the type field. So when I went to click on the add link for the personal information field collection, it failed to find the page. When I changed manually changed the type field to jobseeker in the DB, it worked.