Keep your old phone number

[EwelinaKaplita1]

I upgraded the o2 app, got a new phone and a new number. I don't want a new number, I want to keep my old number. 

[Cleoriff · Accepted solution]

@EwelinaKaplita1 

If you were already an O2 customer then you need to do a sim swap

Guide: Sim Swap: a mini guide 2017 update 

If not, follow this guide Guide: Migration & porting into O2 

If you need help,  contact the sales team as they can help with that – message them on Social Media if that works best for you -on Facebook ( https://o2uk.co/O2CFB) , Twitter ( https://o2uk.co/O2CTW) or Instagram ( https://o2uk.co/O2CIG)

Or you can call them on 0800 081 0255

Guide: How to find help & contact O2 

[Enlli]

Sounds like you did a new contract and not an upgrade.

Follow the advice given re migration