After 5 months of total frustration, I gave up on my new Hornady LNL progressive press. Currently, Hornady has some very serious quality control issues.
I had the same issue you describe here and a dozen more issues that never got resolved. The press simply would not run. I bought a Dillon 550 and it works without issue.
I would call Hornady Customer Service. I don't beleive they can resolve these issues but you should try anyway. When they send parts it takes at least 7 business days, so beware. Most of the time they are nice but "pig" slow.