T-Mobile is facing a lawsuit from New York City for violating the city's Consumer Protection Law.

The lawsuit alleges that T-Mobile has engaged in several deceptive practices through its Metro by T-Mobile prepaid brand. New York City says that it's identified more than 2,200 violations that span across 56 Metro stores from both authorized dealers and T-Mobile's MetroPCS NY subsidiary.

NYC has accused T-Mobile and Metro of selling used phones as new, overcharging or adding undisclosed or illegal activation fees, and including unwanted services like extra lines and mobile hotspot capabilities. The city also accuses T-Mo and Metro of having a "deceptive" return policy that states online that phones have a "30 day guarantee" but then in the fine print says that phones bought in-store must be returned within seven days. The lawsuit also points out that Metro doesn't even sell phones online, so all purchases are made in-store.

"At the same time T-Mobile touts its Metro products and service and its great customer service ratings, its Metro by T-Mobile stores are scamming New Yorkers into buying used phones, tacking on additional costs, enrolling them in financing that’s destroying their credit, and then trapping them with their deceptive return policy and incomplete receipts," said New York City's DCWP Commissioner Lorelei Salas. "T-Mobile’s rampant and repeated deception is made more troubling by the fact that these tactics particularly harm consumers who are simply seeking to find an affordable wireless plan."

T-Mobile says that it's taking the lawsuit "very seriously" and is currently investigating the claims. "What we are seeing alleged here is completely at odds with the integrity of our team and the commitment they have to taking care of our customers every day," the carrier told CNET.

This is the second lawsuit that T-Mo is currently facing from the state of New York. NY state attorney general Letitia James is one of the 17 state AGs who are suing to block the proposed merger of T-Mobile and Sprint. That trial is slated to begin in December.