Hotspot device to cast to TV

Hello. My wife and I are tracfone/ straight talk customers. We have been using our data by enabling the hotspot feature on one phone and casting it to the TV with the other. We were just informed by the straight talk people that they will cancel us if we continue. Since we didn’t know it violates their terms and find this an ideal arrangement : will any hotspot device work for us if we were to purchase one? Thanks