If two sets of dies that had worked fine before are suddenly getting stuck cases, I'd suspect it's a lube problem.
First thing is to get them out. Stuck case removers are dirt cheap if you don't have the makings per 257Roberts.
Once the stuck cases are out, take the dies apart and clean them with solvent. Use a flashlight and check to make sure there's no crud remaining inside.
Switch lube - toss the old stuff, whatever it is. I know I'm partial to Imperial Sizing Die Wax - works wonderfully with less cleanup than anything else I've used, but replace your present lube.
If that doesn't work, call the RCBS help line.