A couple of the roller assemblies (quarter window power windows) have stuck rollers(small ones). What is the best method to free these up?

2007 Dodge Charger R/T, Road and Track Performance Group, Steel Blue 1965 Chrysler 300 Convertible, 383 4V, 727TF, Factory Air, Spanish Red 1964 Pontiac GTO, Tri-Power, 4 Speed, Grenadier Red "What ain't no country I ever heard of. They speak English in What?" - Jules Winnfield