No problem with network here (Dublin 1/7).
Did anything change on your phone - e.g. software or app updates, settings changes etc.?
Make sure that your settings are still correct:
http://community.48months.ie/t5/Internet/My-mobile-data-doesnt-work/m-p/35786
Switch off, take the SIM out, GENTLY clean the SIM contacts, reinsert it, switch on, manually scan for networks and connect to 48 if possible.
Do other services work - outgoing/incoming calls and texts?
Are you using a Samsung? If so then some of their phones seem to have a problem whereby the phone spontaneously "forgets" its APN/internet (and other?) settings and these need to be reconfigured. It seems to be a widespread problem globally which you'll see if you Google about it.
Hope this helps.
