The AT&T Push and fetch emails feature is used to show new emails in your mailbox. So if this setting is disabled or turned off because of your device power, then chances are you will not get new emails on time. There may be chances that you will receive delayed emails, so you need to check for various things to resolve this. The first thing is to unmute thread notification, check for push data, and ensure that the app's background refreshing is ON. With these simple approaches, these issues can be resolved.