Having trouble with a stiff jockey wheel screw drive.  Try servicing or replacing the roller bearing in the screw drive tube makes a world of difference .  Comes as a unit Cost $6.50 not hard to do while in the van park

I had a similar problem and solved it by replacing the whole thing with a hydraulic one....

same with anything, look after it or lose it when you need it most

In my moment if frustration  I seriously looked at that option but $399.00 turned me off  when  offered the  $6.00  onsite fix