Glow Plugs

Hi There,
I went to replace the glow plugs in my freelannder today.
When removing one of the plugs it came apart and the end part stayed inside the head. I tried to pull it out with a plires but failed to move it .
Any advice would be helpful
Thanks

had new injectors in mine a while ago and asked garage to change glow plugs at same time ready for cold winter mornings
garage said the will not budge and if they snap off its most likely head off and drill them out and I don't fancy that idea
sure hope you find a way to get them sorted