Why is there a theme in the place where my Apple phone sends messages?

This situation needs to be an Apple device with IOS5.0 or above, and both parties are networked.

Just put it back in the settings. Find the text message in the settings, and just adjust it inside. If you want to use SMS, just turn it off in Settings-Info-Display Theme.

The specific operation is as follows:

Open "Settings" on the home page and slide down to see the "Information" column;

Click "Information" and you will see "Display Subject Bar";

Click the toggle button until the above picture is closed.

imessage:

That is, you and your mobile phone are both Apple's. There is no charge for sending text messages, but only the internet traffic, but only if your mobile phones are online, and imessage is turned on, and you can also send pictures and videos.

Turn off imessage:

Settings-Information-Just turn off the imessage switch.