@PhoneGuru See this thread: https://community.o2.co.uk/t5/My-O2/MyO2-is-showing-old-phone-as-my-device/m-p/1368555
I DO NOT WORK FOR O2
If your new phone is working as it should do, then check and see if you have a pencil icon next to your device In My O2. If so you can change it yourself.
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