Some Uber customers think Uber is taking them for a ride–and not in a good way. According to a federal class-action lawsuit filed today, Uber is charging UberX riders based on different, less-efficient routes than the ones it’s basing driver pay on, resulting in higher fares for riders. The suit relates to Uber’s “upfront” pricing model, which offers drivers a guaranteed rate based on miles and minutes driven. The complaint, filed in Brooklyn federal court, notes this practice qualifies as unjust enrichment under New York general business law.

“Contrary to Uber’s representations concerning the ‘cost of the ride’ and the “actual fare” charged to Uber X riders via the Upfront Pricing model, Uber has charged Uber X riders a fare that is $1.98 higher on average than the ‘actual fare’, i.e., the fare incurred by the Uber X drivers for the ride,” according to the lawsuit. The complaint estimates that Uber pockets an additional $7.43 million per month from UberX drivers thanks to its upfront pricing.

In September of last year, the Ride Share Guy blog saw a discrepancy between what drivers were being paid and riders were paying, noting that Uber was “overcharging” customers. In the months since, Uber has been pressured to answer questions about this alleged difference. It’s only in the last week that details have emerged. First came the explanation that it had developed a new method of pricing for customers. Uber representatives told Bloomberg the company estimates fares based on what a rider would be willing to pay. In that report, Uber’s head of product, Daniel Graf, said the company uses artificial intelligence to determine these prices. However, the lawsuit from Gayed suggests it’s using elongated routes to craft its fares.

“Upon information and belief, Uber has intentionally designed the software that calculates the Upfront Price to use a longer, less efficient route than the route which Uber uses to populate the driver’s Uber App, which charges the rider a higher fare and pays the driver a lower fare, when the two should be the same fare as set forth in the Technology Services Agreement,” the complaint reads. A similar claim was made in April by a group of Uber drivers.

The new lawsuit is just the latest headache for the ride-hailing company, which just yesterday agreed to pay New York drivers tens of millions of dollars and admitted to underpaying them for over two years. The missed revenue came to light as Uber was preparing to launch a more transparent fare breakdown for drivers.