The Delhi Court, for example, ruled that Prohibition of Child Marriage Act, 2006 overrides all personal laws and governs each and every citizen of India The ruling stated that an under-age marriage, where either the man or woman is over 16 years old, would not be a void marriage but voidable one, which would become voidable at the option of the child entered into the marriage, the Act holds that a child marriage is voidable only upon the filing of a petition for annulment in district court. It is thus deeply problematic that the 2006 Act does not automatically declare child marriages void, only making them voluntarily voidable.
The High Court held that a child marriage is not automatically void under India’s civil laws if entered into by the ‘choice’ of the girl, but that the marriage would be voidable only at the option of the contracting party under the Prohibition of Child Marriage Act, 2006. This loophole thus seems to allow child marriages to continue to be legally valid,
Therefore you can apply for marriage certificate based on the proof of solemnisation of this marriage convince the registrar about the law in this regard.