Are you a lady,as my first thought is they are taking you for a ride.If you put in new glow plugs and then it will not start the
glow plugs are not compatable,they should have put your old ones back.Does the engine sound sluggish on turn over,the battery should be checked,it should be above 12Volts and headlights should not dim on turn over,.could be starter motor as it has not failed,it will not show as a problem,other than that they should be able to squirt cold start spray in the air intake and it should fire if there is a fuel problem.Good Luck.
glow plugs are not compatable,they should have put your old ones back.Does the engine sound sluggish on turn over,the battery should be checked,it should be above 12Volts and headlights should not dim on turn over,.could be starter motor as it has not failed,it will not show as a problem,other than that they should be able to squirt cold start spray in the air intake and it should fire if there is a fuel problem.Good Luck.