What are you sizing them to? Or are you shooting them "as dropped"? What size are they dropping with your alloy? Are you getting any leading, or just keyholing?
Most CZ barrels slug pretty large for 9mm, but they'll eat .358" bullets and larger without any problems in chambering. I've not had great luck with Lee's other bullet molds that work in 9mm. For example, the 356-125-2R keyholed all over the place. I had better results with the TL356-124-2R, but you're forced to use the LLA and I have guns that seem to lead after awhile unless I really make them sticky and keep my loads down. That doesn't leave you much choice if you can't get the 358-125-RF to work.
I've moved on to molds from other manufacturers, like Lyman. Sure they cost more, are heavy, and only come in a max of 4 cavity, but if taken care of, your great, great grand kids could still be using them.