west asset management collecting student loan debt

I was being garnished for student loans and finally my company got notice to cease and desist garnishment in may of this year, I was also told I was owed some money for overpayment by my payroll dept. I called the dept. of education and they said I was paid in full, and that I was due a refund but they couldn't disclose the amount. The next time I called the dept. of education I received a recorded message that says my account is being handled by West Asset Management. So I called West Asset Management and they stated they show my account as paid in full. This has been a couple of months now and I still have not received my refund and the dept. of Education is still saying my account is being handled by West Asset Management, when I think it should be saying paid in full. My question is what is my next step?