The prior year AGI used for your electronic signature does not match what is currently on record with the state of California.
Fix #1: Sign into your PriorTax account and enter the correct AGI amount right on your rejection status page. You can then resubmit for filing.
Fix #2: Your other option is to sign the e-file return using Form FTB 8453/8453-OL. To do this, sign into your PriorTax account and follow the instructions on your rejection status page.