The prior year AGI in the primary taxpayer electronic signature does not match what is currently on record with the state of California.
Fix #1: Sign into your RapidTax account and enter the correct AGI on your rejection status page. Resubmit for filing.
Fix #2: If you do not have a valid AGI or PIN from your prior year return, then follow the on-screen instructions to sign the e-file return using Form FTB 8453/8453-OL.