They said something with the term Sallie Mae in it but called at 6 a.m. which is too early for most businesses. When I asked them what it was regarding they claimed they couldn't tell me without my verification information. Asked for my date of birth and last 4 of my social. I heard many other callers in the background and that made me feel suspicious since the real Sallie Mae can afford cubicles for their callers. They don't have all workers crammed into a sweatshop setting making calls.
If the number is Sallie Mae, tell them to leave a message if you don't answer or you will never call them back. I think there should be certain times at which they can call.
This number calls repeatedly. One would think anyone will legitimate business with you would know enough to leave a message - if they don't they'll never reach you.