So your sim is not working in another phone also ?
Your going to need to phone 02 on 202 for contract customers or 4445 for payg to ensure your account is ok.
Also check here to ensure your masts are working.
http://status.o2.co.uk/If you think the mast is not working even though it says it is then again phone 02 to report it.
I note you have wiped your sim card clean, so you may need a new one.
Either pick one up from your local 02 Store ,or ask customer services to post you one out.
You can perform a sim swap instore or at home. It takes from a few hours to twenty four hours approx for all the services to fully re activate. Typically turning your phone off and on helps to reset the service.
The sim swap link is.
http://swapmysim.o2.co.uk/Hope you get sorted quickly so you can return to enjoying your phone.
