Did an upgrade to Xperia 5II in August, and migrated my old number to the new SIM. When I message/call people it will show up with the new number. Spoke to 02 twice and confirmed only the one contract and they see only one number (my old number I migrated). I also see only one contract in my O2 app.
I've updated my number in message settings.
Any ideas because right now O2 are not being useful in solving this?
If the new sim had a number allocated to it prior to migrating your number, it can get stuck in the phones memory.
You can try migrating your number to a new blank sim or if that fails, a factory reset would be the last resort.
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