Hi mary88 and welcome to the world of the i30.
I have the same problem as you when filling up.
I've found that by placing the nozzle just into the filler neck, turn slightly so the diesel flows down the neck and just a light squeeze on the trigger does the trick.
Had mine for 18 months and no other probs.
PS there is a dedicated i30 forum site which is worth joining.
It's an oz site but plently of Brits and other on it.
Just reached 500 members in less than year
http://www.i30ownersclub.comhttp://www.i30ownersclub.com/forum/