Mystery alert on Messages app icon (iOS 15)

The red exclamation mark on the Messages app icon usually means that a message failed to send. This can happen due to a poor internet or cellular connection, or if there was an issue with iMessage.

Even if you delete your messages, the badge might remain if the app still registers a sending failure. You can try opening the app to look for any failed messages (indicated by a red exclamation mark next to them) and tap "Try Again," or restart your phone to clear the alert.

If the alert won't go away, here are a few things you can try:

• Check for Failed Messages: Scroll through your conversations to see if any have a red exclamation mark next to them. Tap the mark to try resending or to delete the failed message.
• Restart Your iPhone: A simple restart can often clear up temporary glitches or stuck notifications.
• Toggle iMessage Off and On: Go to Settings > Messages, turn off iMessage, wait a few seconds, and turn it back on. This can refresh the service.
• Check Your Connection: Ensure you have a strong Wi-Fi or cellular signal, as a weak connection is a common reason messages fail to send.
• Check for Updates: Go to Settings > General > Software Update, download & install available updates.

Many thanks for your detailed response.

I don't do much texting, as the tiny keyboard on my iPhone 6s (which I use primarily just as a phone, having other devices as well) is a hassle.

There are only 4 messages listed in the app now; none has a red question mark.

Restarting the phone didn't remove the !.

I'm not clear on the difference between Messages app and iMessage. I went to Settings > Messages, saw that iMessage was off (it said something about failure to initialize? Try again). I turned it On, then Off. And the ! disappeared.

Thanks again. 👍