Hi ​@Jamie Hunt, 

I do apologise that the incorrect number is showing on text. Please follow the below to help resolve the issue:
 

For iPhone:
- Please go to Settings> Phone> My Number.
- Please change it to the number you wish to keep. It might not allow to change or save immediately.
- If the number does not change kindly open the Settings app. Tap General. Scroll down to the bottom of the list. Tap Reset. The "Reset" option is at the bottom of the Settings menu. ... Tap Reset Network Settings. Enter your passcode if prompted, then tap Reset Network Settings to confirm your choice. This will help.

For android:
To check or update the number shown on your Android device, please follow the steps below:

📱 Check your phone number in settings
1. Go to Settings
2. Tap About Phone or About Device
3. Select Status
4. Tap My phone number
📌 On some devices, this may appear under SIM Status or SIM Card Status within the Status menu.

💬 Update number in Messages app (if applicable)
If your number is showing incorrectly in messaging:
1. Open the Messages app
2. Tap More (⋮)
3. Select Settings
4. Tap Advanced
5. Select Phone number
6. Enter the correct number associated with your SIM
7. Tap OK to save

🔄 If the number is still incorrect

Please try the following:
* Remove the SIM card
* Restart the device
* Reinsert the SIM card
* Check again in Phone Settings

🔍 Further troubleshooting

If the issue persists after rebooting:
* Insert the SIM into a different device
* Send a text message and check whether it displays:
- Your correct (ported) number, or
- The temporary number

This will help determine whether the issue is with the SIM or the handset.