CDK Global, the company that provides management software for nearly 15,000 car dealerships in North America, is down for a second day following a cyberattack, according to a report from Automotive News. The outage has left car dealerships across North America unable to access the internal systems used to track car sales, view customer information, schedule maintenance, and more.

On Wednesday, CDK told dealerships that it’s “investigating a cyber incident” and “proactively shut all systems down” while addressing the issue. However, CDK restored its systems shortly after, only to shut them down hours later due to “an additional cyber incident.”

Many car dealerships have had to go back to pen and paper while CDK’s software is down. Teddy Morse, the CEO of the Ed Morse Automotive Group, tells Automotive News that the dealer “can still take a piece of paper and walk it over to the technician and get the job done.”

CDK still hasn’t provided any information on the cyber incident that caused the attack — or who’s behind it. In a statement provided to The Verge, CDK spokesperson Lisa Finney says the company will “remain vigilant in our efforts to reinstate our services and get our dealers back to business as usual as quickly as possible.”

There’s still no word on when CDK will restore its service, either. In a message to dealers obtained by Automotive News, CDK says the outage will likely last for “several days.”

Update, June 20th: Added a statement from a CDK Global spokesperson.