The nation's taxpayer advocate told Congress Friday that the IRS is making it more difficult for people to pay their taxes, including by turning away people and their payments at taxpayer assistance centers (TACs) if they don't have an appointment.

"I find the notion of declining to accept tax payments from walk-in taxpayers inexplicable and baffling for a tax collection agency," Taxpayer Advocate Nina Olson wrote in her prepared testimony for the House Oversight and Government Reform subcommittee hearing. "Additionally, it has been reported that TAC employees have refused to assist taxpayers because they do not have appointments, even when there had been no one in the TAC receiving or waiting to receive assistance."

But while she said it's harder to pay in some cases, the IRS is still fining people for noncompliance just as it always has.

"[The IRS] is sending a message that we can't deal with you," Olson told Rep. Stephen Lynch, D-Mass., at the hearing. "And a taxpayer would say, 'Well, if you won't deal with me, I won't deal with you.' The problem with that is the IRS will eventually find you and it will be very unpleasant when that happens."

The agency's decision to cut customer service last year in response to budget cuts contributes to the customer service problem, Olson said. Obamacare also presents a problem, because the IRS hasn't provided needed information to companies that might be required to pay a "stiff" price under the employer mandate.

Just days away from the tax deadline, the IRS also changed a policy that used to make it more difficult for taxpayers to make down-payments on their tax bill.

"The IRS released a memo this week saying [that] if you file an offer-and-compromise and you give us your downpayment, and you're not in compliance with all your tax returns, we are sending the money back to you, we are sending the offer back to you and we are saying get in compliance," Olson told Rep. Mark Meadows, R-N.C. "Yes, it is insane."

The agency is working to develop a program for people to pay their taxes online, something Olson has long supported. But early tests conducted of the program conducted by senior management officials suggest it might lead to more frustration.

"These are people who are fairly sophisticated, financially," she said. "Fifty percent of those volunteers could not get through the online account the first time around."

Difficulty in using the online system, combined with cuts in IRS customer service by phone, could lead people to give up on paying their taxes.

"Rather than designing tax administration around the small minority of taxpayers who are deliberately evading payment of tax, we should design our rules and procedures to make it easier and clearer for the willing taxpayers to comply," Olson suggested.