This is an issue to be resolved by the Islamic court or the authorized
Islamic center.

If your reconciliation was done before the end of her third monthly
cycle and this wasn’t your third divorce to her, her second marriage is
void and she is living in Zina with this man.

Whether you want to stay with such a woman or not this is your own
choice!

Hope you are in best of health and imaan. Me and my wife married in October 2013 but unfortunately in mid october 2016 I gave her one divorce. After that we had rujuu by physical intimacy and foreplay but she denied that rujoo and she married another man. Now my wife and her father brought divorce papers and forced me to sign those. What shall I do?