Why won't my 3 sim work in my Sony Ericsson mobile?
Right now I have an 02 pay as you go sim in my unlocked Sony Ericsson phone it works fine. I've put in my 3 contract sim in and it comes up on the screen "invalid sim". I'm using a very old phone as mine was stolen.
From looking at the sims, 02s has a large chip and 3s is quite small so maybe the phone can't read it? If that's the reason can I request a larger chip from 3? This is second sim I've requested from them after they stupidly sent me an iPhone one.