Navient placed me into deferment status

I am a full-time student in a nursing program and in deferment status for my student loans. At the beginning of my semester Navient placed me into deferment status until 2014 (graduation year) after they received my enrollment documentation from my school. Prior to my semester ending (31 Dec 2012) Sallie Mae started sending me bills for repayment in November. I have already had my school resend the enrollment paperwork as the personnel at Sallie Mae said they do not have my enrollment paperwork. Now it is 3 January 2013, I just got off the phone with them for the 3rd time in two months and they are still saying that I am not enrolled in school. Also they are claiming that they do not have any paperwork from my current semester that started on 1 January 2013 or any paperwork from my previous semester. Each time that I have called the only answer that they will give me is to resubmit my enrollment documentation. I have loans through two other lenders and they are not sending any bills and do have my enrollment forms from my school. The enrollment forms were sent to all lenders at the same time from by my school.