Cell phone service companies, including major players like T-Mobile, as well as third-party retailers like Radio Shack, Wirefly and others have received growing attention due to complex rebate redemption rules. Both carriers and retailers make customers submit rebate claims during a 30-day window, often 6 months after cell phone activation. Some authorized dealers have responded by trying to make rebate requirements more transparent, explaining that the carrier will withdraw payment from them if a customer quits service before the end of the contract.