The top official in charge of the new healthcare exchanges has apologized for the technology problems that have slowed online enrollment. Marilyn Tavenner, the administrator of the federal Centers for Medicare and Medicaid Services, spoke Tuesday before the House Ways and Means Committee.

Marilyn Tavenner: “We know that consumers are eager to purchase this coverage. And to the millions of Americans who have attempted to use healthcare.gov to shop and enroll in healthcare coverage, I want to apologize to you that the website has not worked as well as it should. We know how desperately you need affordable coverage. I want to assure you that healthcare.gov can and will be fixed, and we are working around the clock to deliver the shopping experience that you deserve. We are seeing improvements each week, and, as we’ve said publicly, by the end of November, the experience on the site will be smooth for the vast majority of users.”

Tavenner says the federal and state exchanges have received nearly 700,000 applications for health insurance. But she failed to say how many have actually enrolled, saying those figures will be available next month. During Wednesday’s hearing, Tavenner also faced Republican complaints that the new healthcare law is forcing the cancellation of many existing insurance plans. Hundreds of thousands of people who have purchased their own insurance have reportedly begun receiving notices that their plans will be cancelled or changed because they no longer meet the law’s coverage requirements.