He married her then he found out that her name was false
Question

                I got married one year ago and I fulfilled all the conditions
    of marriage that I was aware of, such as the agreement of the
    woman's guardian, witnesses, the mahr (dowry) and so on.
    Before we got married she told me that her full name was “A M
    D”, as it appeared on her official papers. One year later I
    found out that her name is “A S Y” and that she changed the
    names of her father and grandfather to names that have nothing
    to do with the originals so that it would be easier for her to
    enter the Kingdom, and she made me use her false name for one
    year, and she did not tell me the truth. It should be noted
    that she always lies, even about the most trivial matters. Is
    this marriage contract invalid? Please note that I never heard
    her true name even from her guardian when the marriage contract
    was done.
Praise be to Allah.
      Firstly: 
    

      It is not one of the essential
      parts or conditions of marriage that correct names be used;
      rather it is sufficient to specify the woman to whom marriage
      is proposed and with whom the marriage contract is done. If
      there is some error in the name or a false name is given,
      that does not affect the validity of the
      marriage. 
    

      It says in al-Sharh
      al-Mumti‘ by Shaykh Ibn ‘Uthaymeen (49, 48, 12), in a
      discussion on the conditions of marriage: 
    

      1.
    

      Specifying the partners: because
      the marriage contract has to do specifically with them, the
      husband and wife. It is a serious matter on which rulings on
      lineage, inheritance and rights depend. Hence it is essential
      to specify who the partners are. It is not acceptable to say
      “I give my daughter in marriage to one of your sons” or “I
      give my daughter in marriage to one of these two men: of “I
      give my daughter in marriage to a student in the college.”
      Rather it is essential to be specific. And it is also
      essential to be specific with regard to the wife, and say
      (for example): “I give you my daughter in
      marriage.” 
    

      There are several ways of
      specifying: 
    

      (i)               
      By
      pointing and saying “I give this daughter of mine to you in
      marriage,” and (the groom) says, “I accept.”
    

      (ii)             
      By
      naming her, such as saying “I give my daughter Faatimah to
      you in marriage,” and he has no other daughter by this
      name.
    

      (iii)           
      By
      mentioning her with some distinguishing characteristic, such
      as saying, “My daughter who completed grade ten this year” or
      “My tall/short/fair/dark/blind daughter” and so
      on
    

      (iv)           
      By
      mentioning some real fact, such as saying “I give my daughter
      to you in marriage,” when he has no other
      daughter. 
    

      End quote. 
    

      So in terms of validity, the
      marriage is valid. 
    

      But what this woman did is
      something that is haraam and there is no difference of
      scholarly opinion with regard to that. For a Muslim to
      attribute himself to someone other than his father is
      something that the scholars regard as a major sin, because of
      the stern warnings that are narrated concerning it. This has
      been discussed previously in the answers to questions no.
      638 and 1942. 
    

      What she has to do is repent
      from that action of hers and correct her name. She should
      fear Allah when speaking and not speak anything but the
      truth, for speech may lead to Paradise or to Hell. The Muslim
      has to strive when speaking to seek the truth, justice,
      honesty and fairness. 
    

      And Allah knows
      best.