Rather than offer one of these programs, servicers often suggest loan forbearance, in which the borrower stops making payments temporarily. But because interest keeps piling up on the loan during the forbearance period, this is an expensive alternative. And some private student loan servicers charge a $150 fee to put an account into forbearance.

Servicers say the complexity of federal student loan arrangements creates problems both for their workers who must try to explain these deals and for borrowers who need to understand them.

But servicers receive $600 million a year for their work, and explaining loan terms is surely one of the jobs they are being paid to perform. “For a servicer to see a student loan borrower struggle and not help them get into the right repayment plan is a huge customer service failure,” Ms. Wang said.

It is also a taxpayer risk, given that such practices raise a borrower’s potential to default.

Mr. Wittwer, who lives in Philadelphia, said he had encountered difficulties with some of his loan payments even though he arranged for them to be deducted automatically from his bank account last year.

“After six or seven months, I get a late notice for my federal loans and I go in to my bank and double-check that the loan was being paid,” he said. “My loans had been transferred to another office, but the original office had kept collecting it.”

It took about a month to fix the problem, Mr. Wittwer said. “You have to be hypervigilant about it because student loans are constantly being sold and moved.”

Ms. Dundon of the Center for Responsible Lending said that the Education Department had fixed some of the problems in its servicing contracts but that financial incentives were still misaligned in certain areas. For example, service companies receive more money if the loans they oversee are being paid off, and less if borrowers stop paying. While this system encourages servicers to keep borrowers current — a good thing — it discourages them from working with borrowers who fall behind.