Check your internet/APN settings. If the APN field has changed from 48months.liffeytelecom.com then edit it, change it back to that, save the settings, reboot and see if data starts working. If it doesn't then you'll have to contact 48 support. See the link in my signature below. Unfortunately some people never get data working when roaming in the EU on a Guido membership even though it should just work.
Hope this helps.
I am not a 48 employee so if you need to contact 48 support then use option 3 or the chat facility here.