You can get new documents with correct name from issuing institutions by showing the affidavit. when you will have all documents corrected, then apply.
I think you can apply only if your college is independent and can issue certificate such as "University College London" which does not require any university to issue certificate.
They issue a new one only if your current one is lost. I contracted manchester university which was my ielts centre and they replied by saying that. I believe in that case previous one will be cancelled