Number on O2 account correctly changed but not on my phone itself

[Oz02]

I recently had a transfer of ownership from my mother’s O2 account to create my own, this meant keeping the same phone number. I called and got it successfully transferred onto my account but my iPhone still says my number is the temporary one that came with the ESIM. What is the reason for this? How can I fix it?

[MI5 · Accepted solution]

@Oz02 

Settings >Phone >My Number.

Edit, save and reboot.