Facebook was sued in the United States over misleading advertisers about the average time users spent viewing online video clips.

Facebook in September 2016 announced that it had inflated the metric for marketers, and said it fixed its calculations. Crowd Siren, the online marketing agency that sued over the misrepresentations, now claims that Facebook knew as early as 2015 that it was over-reporting the figures.

Crowd Siren added fraud claims and a request for punitive damages against the company in an amended complaint filed Tuesday in federal court in Oakland, California.

Facebook didn't correct the inflated metrics, according to the court filing. Instead, the company engaged in a public relations campaign to deflect attention to the errors, Crowd Siren said, citing internal company documents and email exchanges.

Facebook also faces allegations in a complaint filed in August that it misrepresents advertisers' estimated audience reach.