Hi ​@Neil62, 

Thank you for reaching out. I do apologise that you are able to send text and activate iMessage. Please follow the instructions below to help resolve the issue:

1. Could you please go to Settings > Phone > My Number
2. Please update this to the number you wish to keep. Please note, the device may not allow the change to save immediately this is expected in some cases.
3. If the number does not save straight away, I’d like you to reset your network settings to refresh the connection:

• Open Settings
• Tap General
• Scroll down and select Transfer or Reset iPhone
• Tap Reset
• Select Reset Network Settings
• Enter your passcode if prompted and confirm

For the iMessage issue please click on the link below:
 

Owethu