Colorado’s U.S. Sen. Cory Gardner said Tuesday he plans to introduce bipartisan legislation aimed at forcing the Department of Veterans Affairs to pay benefits to student veterans who have been shorted because of the VA’s information processing and accounting difficulties.

“The VA let these veterans down and this cannot be tolerated,” Gardner said in a statement. “First, the VA made a mistake and did not properly pay student veterans the money they are entitled to; and now the VA is failing in their responsibility again by not providing a plan to pay those students back quickly.”

The Colorado Republican and U.S. Sen. Doug Jones, an Alabama Democrat, are co-sponsoring the Fix Immediately Outstanding Underpayments for Student Veterans Act, which would establish a VA commission to audit monthly payments to student veterans and require that students who have been underpaid are made whole.

The VA hasn’t been paying some student veterans the full benefits they’re entitled to under a 2017 law that boosted benefits and changed the way certain housing payments are calculated.

NBC News reported last week that VA officials had been telling congressional staff that they wouldn’t make retroactive payments to veterans who were paid less than they were owed, but VA Secretary Robert Wilkie later insisted the government will set things right once it gets its systems in order.

The Gardner-Jones bill includes a provision to prevent the VA from taking back money it overpaid in error.

Gardner sent Wilkie a letter in late October demanding the VA fix the problems after student veterans at Colorado Mesa University brought the underpayments to his attention.

“Most problems Congress addresses are complicated and do not have one ‘right’ answer,” Gardner said in a statement Tuesday. “This is not one of those issues. To me, it’s pretty clear what the right thing to do is: Congress must act to ensure our student veterans receive every penny they are entitled to.”

The VA encourages students encountering problems with their GI benefits to call 1-888-442-4551.