chocandpatience-
My experience and knowledge are for U.S. fixtures and voltages, but I think we can reasonably assume that the principles work the same elsewhere.
The problem can be with a bulb, the ballast (a transformer used by fluorescent fixtures), or (much less likely) a loose connection.
Since bulbs are much easier and cheaper to replace than ballasts are, the first thing to do is change the bulb(s) and replace them with bulb(s) that you know are working.