Bringing my old number to o2

[KP13]

I spoke to o2 on Friday and the lady processed my swim swap as I gave her the PAC code etc, she told me it would be done on Monday as it takes 1 working day and won’t process over the weekend.
My old sim lost service about 30 mins ago and my new one is working however on the phone and ‘my number’ section on my settings it still has the new number (not the one I’m wanting to use) and the same with my o2 app it still has the number that o2 sent me. Will this change or is that normal?? 

[MI5]

@KP13 

Keep rebooting your phone until the changeover is complete and everything updates.

It can take up to 24 hours to fully changeover.

If you have an iPhone you need to change your number in Settings >Phone >My Numbr.

If it's Android, your number won't change on the phone.

[KP13]

Thank you I will keep doing that and bare that in mind. I have tried changing it via settings but when I go off and back onto it it changes itself back to the original number. When people text my number I am wanting to bring it comes through on my new phone however when I reply they see the new number 

[MI5 · Accepted solution]

@KP13 

You need to save the changes by pressing "done" and then reboot.