It didn’t receive the same attention as some of Facebook’s other recent controversies, but the company was rocked last year by a bombshell report from ProPublica that discovered advertisers could request racially discriminatory ads. Now, a follow-up report from the publication found that the practice is still going on.

Facebook promised in February that it would start strictly enforcing its rules regarding discriminatory ads. However, just last week, ProPublica bought dozens of Facebook housing rental ads and asked that they not be shown to African Americans, Jews, Spanish speakers and other groups. And all of the ads were approved by Facebook in a matter of minutes.

By Facebook’s own rules, these ads should’ve been denied, and the publisher should’ve been required to provide self-certification. However, neither happened. For its part, Facebook acknowledged that what happened was a mistake.

“This was a failure in our enforcement and we’re disappointed that we fell short of our commitments,” Ami Vora, a vice president of product management at Facebook, told ProPublica. “The rental housing ads purchased by ProPublica should have but did not trigger the extra review and certifications we put in place due to a technical failure.”

Whether it’s a “technical failure” or not, Facebook needs to take this issue seriously and correct it once and for all.