Try a manual network search for alternative local networks and also reboot the phone a few times to see if it connects.
If your apn is idata.o2.co.uk try changing it to mobile.o2.co.uk or vice versa.
Check if you have data enabled for safari or the app you are trying to use as individual apps can be restricted in settings.
Hey @Anonymous and @Anonymous are you still having problems connecting to the networks today?
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@Anonymous OK I'm not aware of any widespread issues but will double check with the rest of the team 
→ Access for You: Registration - Find out how to register for our Access for You service.
→ Want to chat with other fellow-minded members? Head to our Off-topic section for some interesting chit-chat.
→ Check out our Priority board for tickets & offers updates, and to discuss all things Priority-related!
→ Welcome to O2! - New to O2? Find out all you need to know to get started!
If you'd like to take part, why not register?
Something we often find (which has been confirmed today) is that users are on the wrong data bolt on - hence my suggestion to harmlessly change your apn.
You can look in your MyO2 http://www.o2.co.uk/myo2 under your tariff bolt ons and check if you have the correct bolt on for your phone (iPhone data for iPhone or standard data for Android and other devices).
Once the correct bolt on is selected, your data will work both home and abroad without any issues.
@HW2018 wrote:
Thanks MI5, changing the data network setting from ’idata’ to ‘mobile’ worked for me :-)
Pleased to hear it mate 😁
