What is does a red circle with a white exclamation mark in the under message’s mean

That means that the text message near that Red Circle / Exclamation Mark did not get sent.

Axel F.

Good evening Jr1faith,

Welcome to the Apple Support Communities!

It sounds like you are seeing an exclamation mark indicating an issue with a message you are trying to send.

The resource below explains what to do about this. Key information is highlighted for you below. Click the link for complete details.

If you can't send or receive messages on your iPhone, iPad, or iPod touch

"If you see a red exclamation point

If you try to send a message and you see  with an alert that says Not Delivered, follow these steps:

1. Check your network connection.
2. Tap , then tap Try Again.
3. If you still can’t send the message, tap , then tap Send as Text Message. Messaging rates may apply. Contact your carrier for more information."

Take care.