My CA state return keeps getting rejected and I am not sure why. Any insight?

Well for one thing the IRS will not begin to accept federal returns until January 24, and a state return cannot be e-filed or accepted until your federal return has been accepted by the IRS.   So right now it is impossible for CA to accept your return.

Is the real problem that your state's forms are not all ready?  Many state forms are still not ready this early and you have to wait for them.

https://ttlc.intuit.com/community/forms/help/state-forms-availability-table-for-turbotax-individual-personal-tax-products/00/26227

I actually just received an update from Turbotax that there is a known error submitting the form that keeps getting rejected. The update advised to wait until January 20 to attempt to refile.