1 pole wont go down

[Chonte]

I have a 1996 1207. 3 of my poles will go down but the rear right wont budge.
The cables are all intact,
I have made sure it is level, tried to push it a bit. But to bo avail. If I try to move the others by hand there us some give but not on the forth.
I saw another post here that said something about greasing the zerks.
I’m a newbie but determined to learn/know how to handle these things on my own. I dont wanna call in the pros till I have tried everything so please.
Heeeeeeeelp lol
Where are these zerks?
What could cause 1 pole to not move?

[southpawma]

Occasionally one of my poles gets stuck as well. I make sure to always have a flashlight and a long screwdriver onboard.
What happens with mine is the "spring" that is inside the pole gets caught on the way down...usually at the spot where the wall track meets the floor track. I use the flashlight to see and the long screwdriver to help guide the spring past this point.