Student loans are often sold or transferred to different servicers. When this happens, your old tradeline should be paid off and show a closed/paid/transferred in the comments and a new one should appear. It sounds like you could have two, or even three (it's not clear if there is just a name change or an actual change of servicer) tradelines for your loan.
Make sure that your IBR enrollment has transferred properly and that you have updated contact information with your current servicer at all times. Checking now might save you some surprises later.
