Dependent SSN or DOB is either incorrect or does not match what is currently on file with the IRS and Social Security Administration.
Fix #1: Sign into your PriorTax account and update the currently reported SSN and/or DOB right from your rejection status page. Resubmit for filing.
Fix #2: Sign into your PriorTax account and remove the dependent entirely from your tax return. Resubmit for filing without claiming the dependent.
Fix #3: If the information you have entered already seems to be correct to the best of your knowledge, you may need to paperfile for this tax year. You should also contact the Social Security Administration to see that the information they have in their database is correct.