Why does iMessage show undelivered?

If you mean that when the iPhone sends a message, the prompt has not been delivered, there may be the following situations:

1, confirm that the signal is normal and close the flight mode.

2. Check whether the SIM card status is normal.

3. Check whether the send key is displayed in bright color and clickable.

4. If you can't click Send after entering the text, the "Send" key is still gray. Please turn off "Show Subject Bar" in Settings > SMS >.

5. If you send text messages to multiple people and manually enter numbers, please make sure to use line breaks instead of spaces to separate each number.

IMessage is an instant messaging software launched by Apple, which can send short messages, videos and so on. It has high security. Different from the SMS/MMS service of operators, users only need the data support of WiFi or cellular data network to complete communication. The specific operation method is as follows:

1. Open the settings.

2. Then click "Info".

3. After entering "Information", click to open the imessage information switch.

4. After setting, open the information on the mobile phone desktop.

5. Then click the "Write Letter" button in the upper right corner of the screen.

6. Then enter the other person's mobile phone number.

7. Edit the information content and click Send.

8. In this way, the imessage message was successfully sent.