My wife and I married in 1991. At the time the Vicar made a **** up with the certificate.
My wife's mother remarried after my wife was born, so our marriage certificate should have read "Smith, known as Brown". Instead it reads "Brown, known as Smith".
Contact your registry office and the error can be corrected by 'marginal notation' - your wife will probably need to provide her birth certificate and other identification such as driving license or passport.