A “majority” of the back-end healthcare.gov bugs preventing insurers from receiving accurate information on Obamacare enrollees have been fixed, the Centers for Medicare and Medicaid Services announced on Wednesday, but the agency declined to share the error rate for those issues.

CMS spokeswoman Julie Bataille said that “with the fixes in place we are generating 834 forms and believe that a majority of the issues that caused inaccuracies previously have been resolved.”

Bataille said the tech team had “knocked out a significant number of bugs.”

“Insurers are now testing those changes to see that they agree and allow us to make other modifications as needed,” she added.

Bataille was pressed by reporters to share the error rate on 834 forms and explain why many incorrect applications had been sent to insurance providers, but refused to do so.

She said only that CMS was “actively working with the issuers now” to review the changes that had been made.

Bataille could not explain why the administration, which has been able to tout specific figures for the number of website visitors and enrollees, could not provide data on the 834 transmission form glitch.

In a joint statement released Wednesday afternoon, CMS, America’s Health Insurance Plans — the top trade lobby for health insurers — and the Blue Cross Blue Shield Association said that ensuring that all Americans received coverage is a “top priority for all of us.”

“We are working together closely to resolve back-end issues between health plans and healthcare.gov. This is a very focused effort that is being driven by a team of experts from CMS, key outside contractors working closely with health plan representatives and overseen by CMS’s general contractor, Optum/QSSI,” the statement read. “We will report on our progress.”

The healthcare.gov website has been plagued with technical problems since its launch, undercutting public support for the health care law and leading to enrollment figures far short of administration expectations.

On Sunday, the administration said the effort to fix the site had succeeded and that it was now functioning properly for the vast majority of users.

The website is now capable of handling 50,000 users at one time and the tech team instituted a queuing system that helps redirect visitors to return during less busy times to more quickly register.

Insurers though say that there are many back-end issues remaining, in particular with the “834 forms” that transmit data on enrollees and what plans they have signed up for. Many of those forms were incomplete and inaccurate, and insurers say those mistakes are delaying enrollees from receiving coverage on time.

On Tuesday, CMS said they've made “tremendous progress” on fixing the issue. But other website problems remain. Reuters reported on Wednesday that the back-end process that transfers subsidy payments for consumers to insurance providers was unfinished.

Bataille on Wednesday, though, touted the website’s stability for consumers and said that they had seen traffic surge since the website was relaunched on Monday.

She said there had been 950,000 visitors on Tuesday, following 1 million Monday visits. Healthcare.gov “continues to experience strong demand,” said Bataille, noting that there were 310,000 visits to the site since midnight, a figure that was 80 percent higher than traffic a week ago. She also said that 790,000 visits were made to a new “window shopping” page the administration says makes it easier for consumers to get information about health plans.

Bataille though declined to confirm a report from Politico that 29,000 people have enrolled in Obamacare exchanges over the last two days, a sizable jump from the website's enrollment for the entire month of October. She said the administration is working to validate recent enrollment figures.

This story was published at 2:23 p.m. and has been updated.