A common problem is that taxpayers with multiple last names (especially Hispanic taxpayers) is that the taxpayer considered one name to be the last name while the Social Security Administration (SSA) (and by extension the IRS) thinks that the other name is the last name.
You can test this by changing your last name on the tax return to the other "last name" and trying to e-file again.
You can try visiting the local tax office (if one) (see https://www.irs.com/articles/contact-the-irs) to ask what they think your name and SSN are (bring plenty of ID).
Alternatively, if nothing helps, you will have to print and mail your return, because even if you discover that the IRS has the wrong last name or SS number, they won't fix it any time soon.
