A myth gets recycled from time to time which factcheck.org boiled down into the the following question and answer:
Q: Is it true that members of Congress, their staffers and their family members do not have to pay back their student loans?
A: Not true. Some congressional employees are eligible to have up to $60,000 of student loans repaid after several years — just like other federal workers. But that’s not the case for members of Congress or their families.
A Snopes article covers the same topic and says pretty much the same thing.