First thing is to spray some CLP around and under the extractor if you can. To get any build up of crud from beneath it. Use the little red tube so it kinda blasts down in there. WD-40 will tell you if it's going to work or not.
Then try it and see how it works.
I'd say next is check the edge and see if it still has a good gripping surface or if it's worn down quite a bit. Could be about time for a replacement.
Check the spring if it has one. Could be weak.
Could be a little bent also.
Jope that helps a little.
George