Notice period

I am a sales manager in a limited company working for more than two years. Travelling daily to various markets of eight districts is a part of my job and myself and all my family members were tested covid positive because of my travel as no other person of my family goes out except me. Though I was performing well ( including April 20), I came to know that my company recruited a new person for my position keeping me under guise and denial (because of politics of my immediate superiors) when myself and all my family members were in home quarantine and myself working from home. As I come to know through reliable outside sources that the new person was going to join the next day, I submitted my resignation one month back giving 3 months notice as per the policy of our company stating my last working day clearly -considering that as humiliation to me and to safe guard my pride and dignity. For the past one month they did not respond to my resignation and subsequent follow up mails and suddenly they sent my resignation acceptance mail yesterday stating that my last working day would be tomorrow as I introduced all the markets to the new entrant for the past one month. They stopped my last month salary also. Considering my family needs, I want to work for the full notice period of three months and do not want to forego two months salary as I am still in search of a new job in this covid time. Kindly advise me how to tackle this situation to work for three months or to get three months salary.