What happens if your marriage license has an error on it?

It depends on when you discover the error. In North Carolina for example, if you discover the error after the license has been filed the license can be amended. Depending on the complexity of the error affidavits may need to be filled out and submitted. There is usually a small fee to amend the license. Call your local Registrar's or Clerk's office where the license was issued and ask them.