Problems ringing other o2 contacts

[Justmebre]

Why  do i get number not recognised when i ring  friends that are also on o2  or they  get same when ringing me  

[pgn]

If your friends live nearby, on the same O2 mast as your phone uses, then: Guide: Is the network down for me or everyone? 

Other possibilities are your SIM card needs a gentle wipe with a cloth, Guide: How can I sort out my network issues? may help.

If you are PAYG, do you have credit on your phone (or an active Bundle?).

Does your MyO2 help? https://accounts.o2.co.uk/signin

Otherwise reach out to O2 via either of the Social Media links just below, @Justmebre 

[Oxonian]

If you think that it might be a network problem @Justmebre :-

My Network App - Find Out More About Your Network Coverage | Apps | O2

https://www.o2.co.uk/apps/my-network

Understand your network coverage

With the My Network app you can keep an eye on your coverage, wherever you are. Download the app and you’ll be able to:

- check the status of our network in your area – you don’t even need to enter your postcode

- test your network speeds

- report any issues with your service.

It’s simple to use and means that you can check the network without having to visit the main site or even enter a postcode.