WASHINGTON (Reuters] – Two active antitrust senators, Richard Blumenthal of Democratic and Amy Klobuchar from Democratic, sent Tuesday’s letter to the U.S. Justice Department requesting that officials investigate possible anti-competitive actions taken by Live Nation, which has ticketing giant Ticketmaster.

These lawmakers cited Live Nation’s past violation of an agreement made with the Justice Department in 2010 that permitted the controversial merger between Ticketmaster and Live Nation. The deal was reached and Live Nation agreed to cease retaliation against venues who do not use its Ticketmaster service at all events.

The legislators asked the department for an assessment of Live Nation’s compliance in accordance with the amended consent decree.

American consumers face skyrocketing ticket costs, unclear terms and high fees as more live events are added. Live Nation has dominated the ticket market, and especially in entertainment venues, since its 2010 merger of with Ticketmaster.” They wrote Jonathan Kanter to Kanter from the Justice Department Antitrust Division.

Live Nation was dismayed to learn that Rival had been purchased by Live Nation, a ticketing company that was meant to be competitive with Ticketmaster.

“We are deeply concerned that the Department’s past enforcement and negotiated remedies in this industry have failed to adequately foster and protect competition in live entertainment and ticketing markets,” they wrote.