Does anyone know of a 2G/3G cell network in the US? Its would be cheaper and I know I avoid my phone a lot when it reverts to 3G when I run out of 4G data. I st

Does anyone know of a 2G/3G cell network in the US? Its would be cheaper and I know I avoid my phone a lot when it reverts to 3G when I run out of 4G data. I still want email, uber etc though.