If you are on a Guido membership and calls and texts are working ok then check your internet settings, if the APN field has changed from 48months.liffeytelecom.com then edit it, change it back to that, save the changes, reboot the phone and see if data starts working.
This is a common problem for some people roaming in the EU on a Guido membership even though it should just work.
And my suggestion fixes it for many but not all users.
Hope this helps.
