Karen,
I was not able to take my Felco's apart because of my weakened hands. A good friend was able to... and found a tiny piece of metal shaving wedged way down between the blades. Just enough to cause the sticking. No way to know it was there without taking them apart.
While he had them apart, he really cleaned them and then lubricated them. Was able to give the blades a really good sharpening. Better than I was able to when they were assembled. When he put them back together, he put on a new spring and a couple other parts I ordered for them.
They have a couple of really small parts inside and were a bit tricky to get back together. Glad I took a video of taking them apart to refer to!
Result?