AT&T is an excellent web-based email service that several people use. Although, many users experience ATT email not working problem on iPhone. If you want to explore the methods for solving this issue, then first, a proper internet connection is necessary to access AT&T email services on iPhone to get rid of this error. Hence, you must first check your internet connection and try to make a stable connection. Further, switch off your iPhone when the AT&T email stops working. Then restart your device and try to re-access AT&T, as restarting your iPhone might solve the problem.