Why didn't Apple send a message to remind you?

Check whether message reminder is turned on in the settings. If it's not turned on, you won't get a reminder.

Specific steps

1, open the settings.

2. Locate the notification option and click Notify.

3. Find information in the notification options.

4. After finding the information, click Enter, and all options such as notification, sound, icon mark and screen lock display will open.

When all are turned on, the mobile phone can receive SMS notifications.