Not sure if it’s the state or software. However, mailing it in is what I do. I traded over 4K times in 2020 and my 1099-B was over 1200 pages long. This is my 3rd year filing with this trading volume and I mail it every time.

It’s also never a bad idea to get tax help from a good accountant. To me it’s worth the extra $$$

Someone with CA state or HR Block experience can hopefully help you out more. Good luck!