Can a non-virgin girl ( who had commited zina when she was 9 or 10 year old or maybe less than that) marry herself without the knowledge of her father? The father however had told the girl if the same guy would send the proposal he is then in agreement with her nikkah being done with him but when the nikkah agreement was done the father had no knowledge about it.

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

It is not permissible for a woman to marry without the permission of her guardian, according to the view of the majority of jurists, contrary to the view of Imam Abu Haneefah . We adopt the view of the majority of scholars in our fatwa due to the strength of its evidence. It is reported in In Musnad Ahmad and others, that the Messenger of Allah, sallallaahu`alayhi wa sallam, said: “Any woman who gets married without the permission of her guardian, her marriage is invalid, her marriage is invalid, her marriage is invalid...”

There is no difference in this ruling between a virgin and a non-virgin.

And the father has to marry her off to one who is suitable for her, whether he is the one with whom she committed Zina or someone else. In case she has lost her virginity, she is not obliged to tell her fiancé about it, except if he stipulates virginity. Rather, she can hint that it was broken as a result of something that happened to her as there are many reasons for the loss of virginity, such as jumping, menstruation, and so on.

Allah knows best.