Starting Issue

Hi

having issues starting my car today,

issue was the car started then after a few secs it cut off, has done this for a couple of starting attempts.



breakdown couldn't find anything so car is at a bmw specialist. any ideas,



car is a 06 reg 320i and done 59000 miles. I have changed the spark plugs on Saturday. car was working perfect after spark plugs were changed as I drove it yesterday and Saturday.



thanks