Thank you for giving me the opportunity to assist you. I will give the best answer that I can with the information provided.
It is entirely possible that you are using the correct SSN, but that number has been used on another return, either because of fraud or by accident. You will need to mail in your return--it cannot be e-filed with that SSN. Another option would be to efile using married separate status, and then amend the return later to include your spouse.
Since you have not filed a return yet, you do not need to amend your return. Youwill not be able to efile his return separate, because it will reject. I think your refund would be processed faster if you mail the joint return in. The other option is to efile yours separately, and then amend your return to a joint return, which will need to be mailed in.