A U.S. Appeals Court on Friday reversed a lower court decision and allowed a class-action lawsuit against Cingular Wireless to go ahead. The ruling relates to a case filed in February 2006 by cell phone user Kennith Shroyer, who complained about how Cingular, now part of AT&T Inc., dealt with customers after it bought AT&T Wireless in 2004.

When AT&T Wireless customers complained about problems related to their service Cingular told them it would give them a chip to improve service if they signed a contract with Cingular, according to an Appeals Court document.

But in doing this, Cingular told the class action members that they would not be able to keep the same rates they had from AT&T Wireless, according to the document.