A friend has just moved network providers, she has retained her number, but while it was being transferred, you get a temporary number.
One it had all moved across, the phone calls and SMS messages would come from her original number, but when it was an iMessage it would come from her temporary number, plus she could not be reached via Facetime.
To fix the iMessage first, I went to Settings -> Messages then I turned iMessage off. Once that had switched off, I then turned it back on. Once it was back on I went down to "Send and Receive" then from here I could see her original number. I also enabled her email address so we can contact her via those as well.
Facetime was the same process, Settings -> Facetime, switch it off then switch it back on and check the addresses have changed.
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