Message not delivering

Hello Summerr_Y,

Thank you for using Apple Support Communities. When you see this occurring, is it affecting all your messages or is this only occurring with one specific contact? If this is occurring with all your messages, then we can recommend the following steps to help out sort this issue out: If you can't send or receive messages on your iPhone or iPad - Apple Support

1.) Close the Messages app.

2.) Restart your iPhone. This step can help refresh things.

3.) Install any pending updates. Keeping your device updated can help fix various issues.

4.) In the Settings app, tap Cellular. Make sure that your phone line is turned on. If you use multiple SIMs, make sure that the phone number you want to use is selected and turned on.

5.) In the Settings app, tap Messages. Turn iMessage off and then back on.

6.) Tap Send & Receive.

7.) Tap the phone number that you want to use with Messages.

If you confirm, this is only occurring with one specific contact, this most likely just means that the message hasn't been delivered yet. For example, if the contact you're trying to reach has their device turned off. It will not be delivered until the device is powered back on.

We hope this information is useful. Thank you for using Apple Support Communities. Take it easy.