If someone could not hear Parshas Zachor because of illness and overslept or forgot, what should one do?

Since listening to Parshas Zachor is a Biblical obligation, one should make every effort to go immediately to another minyan that davens latter and hear it there. If that cannot be done, Mishna Berura (685: 16) quotes Magen Avrohon that one should ‘Bedieved’ after the fact hear and then have intention to comply with the similar reading of ‘Vayovo Amalek’ that is read during Purim. Nitei Gavriel mentions in the name of the Chassam Sofer that if there are three people who did not hear Parshas Zachor during Shabbos morning, as explained by Horav Shlomo Miller Shlit’a, they may ask the shul attendants to read it by Mincha instead of the next week parsha of Ki Teitzeh. Poskim disagree as to the obligation of women to hear Parshas Zachor. Yet it is accustomed that they do.